The United Kingdom has started supplying Ukraine with anti-tank weapons, and Canada has reportedly deployed a small contingent of special forces to Kyiv amid concerns over a possible Russian invasion.

British Defense Secretary Ben Wallace said light anti-armor defensive weapons systems would be supplied to Ukraine, with a "small number" of U.K. personnel traveling to the country to provide training.

The announcement came after he warned tens of thousands of Russian troops are positioned next to the Ukrainian border, explaining the deployment is "not routine" and they are equipped with tanks, armored fighting vehicles, rocket artillery and short-range ballistic missiles. He told members of parliament there is "real cause of concern" over the scale of the force being assembled by the Kremlin, supported by Russian air and maritime forces.

Russia's presence and levels of readiness are contributing to a "destabilizing and coercive atmosphere that risks miscalculation at best and at worst conflict," Wallace added. He invited his Russian counterpart, Sergey Shoygu, to visit London "in the next few weeks" to discuss "issues related to mutual security concerns and engage constructively in good faith."

After highlighting previous work as part of Operation Orbital, the U.K.'s training mission in Ukraine, Wallace outlined new support being provided. He told the House of Commons, "In light of the increasingly threatening behavior from Russia and in addition to our current support, the U.K. is providing a new security assistance package to increase Ukraine's defensive capabilities.

"We have taken the decision to supply Ukraine with light anti-armor defensive weapons systems. A small number of U.K. personnel will provide early-stage training for a short period of time, within the framework of Operation Orbital, before returning to the United Kingdom," he said. "This security assistance package complements the training capabilities Ukraine already has and those that are also being provided by the U.K. and other allies in Europe and the United States," he added.

"Ukraine has every right to defend its borders and this new package of aid further enhances its ability to do so," he said. "Let me be clear: This support is for short-range and clearly defensive weapon capabilities; they are not strategic weapons and pose no threat to Russia; they are to use in self-defense," he cautioned.

Ukrainian Defense Minister Oleksii Reznikov welcomed Wallace's announcement, saying that Kyiv "highly appreciates Britain's decision to provide a new security package."

Britain has previously warned Russia of severe consequences if it launched a new military assault on Ukraine while offering financing to enhance Ukraine's naval capabilities.

Western countries say they fear Russia is preparing a pretext for a new assault on Ukraine, which it invaded in 2014. Moscow denies any plans for an attack but has said it could take unspecified military action unless the West agrees to a list of demands, including banning Ukraine from ever joining NATO. Talks last week ended with no breakthrough. Kyiv has asked Western countries for arms to help it protect itself.

Canada has also made a contribution to safeguarding Ukraine by deploying a small contingent of special forces operators, Canadian Global News reported on Monday, after security talks last week ended without a breakthrough. The Canadian special operations presence is part of an attempt by NATO allies to deter Russian aggression in Ukraine and to identify ways to assist the Ukrainian government, Global News reported, citing unspecified sources.

The unit has also been tasked with helping to develop evacuation plans for Canadian diplomatic personnel in the event of a full-scale invasion, Global News said.

A spokesperson for the Canadian Special Operations Forces Command said it could not confirm the report but said it has supported the Ukrainian security forces on a periodic basis since autumn of 2020.

Canadian Foreign Minister Melanie Joly was in Kyiv to discuss efforts to deter "aggressive actions" by Russia and met Ukrainian Prime Minister Denys Shmygal on Monday.

Canada, which has the world's third-largest Ukrainian population after Ukraine and Russia, has maintained a 200-strong training mission in western Ukraine since 2015. On Sunday, it urged Canadians to avoid nonessential travel to Ukraine, in a new advisory citing "Russian aggression."

Russia denies evacuating embassy staff

Meanwhile, Russia said on Tuesday its embassy in Kyiv was operating as usual following a New York Times report that Moscow had begun evacuating the families of staff at its diplomatic missions in Ukraine, the Interfax news agency reported.

The New York Times cited a senior Ukrainian official as saying that 18 people, mostly family members of Russian diplomats, had left Ukraine on Jan. 5. It said around 30 others left the embassy in Kyiv and the consulate in Lviv in western Ukraine over the next few days.

The U.S. newspaper also reported that diplomats at two other Russian consulates had been told to prepare to leave Ukraine. The Russian Foreign Ministry did not comment on its consulates in Ukraine but told Interfax that its embassy in Kyiv was operating normally. It did not provide further detail.

The Ukrainian Foreign Ministry said it had not received any information from Moscow about the evacuation of employees from its diplomatic outposts in Ukraine. It added that Kyiv had no plans to evacuate Ukrainian diplomats from Russia.

Meanwhile, Russia's top diplomat strongly rejected U.S. allegations that Moscow was preparing a pretext to invade Ukraine, as Russian troops that are amassed near the Ukraine border launched more drills Monday.

The White House said Friday that U.S. intelligence officials had concluded that Russia had already deployed operatives to rebel-controlled eastern Ukraine to carry out acts of sabotage there and blame them on Ukraine in a "false-flag operation" to create a pretext for a possible invasion.

Speaking to reporters Monday, Russian Foreign Minister Sergey Lavrov dismissed the U.S. claim as "total disinformation."

He reaffirmed that Russia expects a written response this week from the U.S. and its allies to Moscow’s request for binding guarantees that NATO will not embrace Ukraine or any other ex-Soviet nations, or station its forces and weapons there.

Washington and its allies firmly rejected Moscow's demands during last week’s Russia-U.S. negotiations in Geneva and a related NATO-Russia meeting in Brussels, which were held as an estimated 100,000 Russian troops with tanks and other heavy weapons are massed near Ukraine in what the West fears might be a prelude to an invasion.

Amid the troop buildup, Russia in recent weeks has held a series of war games in regions that border Ukraine. On Monday, the military announced the launch of another exercise involving armored units stationed in the western part of Russia that includes 300 combat vehicles. A delegation of U.S. senators is visiting Ukraine to emphasize U.S. support for the country.

"Our bipartisan congressional delegation sends a clear message to the global community: the United States stands in unwavering support of our Ukrainian partners to defend their sovereignty and in the face of persistent Russian aggression," Sen. Jeanne Shaheen, a New Hampshire Democrat, said in a statement.

Sen. Richard Blumenthal, a Connecticut Democrat, said after the delegation met with President Volodymyr Zelenskyy, that if Russia invades Ukraine "we will impose crippling economic sanctions, but more importantly we will give the people of Ukraine the arms, lethal arms they need to defend their lives and livelihoods."

Speaking Monday on a visit to Kyiv, German Foreign Minister Annalena Baerbock warned that "any further escalation would carry a high price for the Russian regime – economic, political and strategic," and emphasized the need to continue negotiations.

"We are prepared to have a serious dialogue with Russia because diplomacy is the only way to defuse this highly dangerous situation," she added.

Baerbock said Germany has offered to send cybersecurity specialists to Ukraine to help investigate last week's cyberattacks, which Ukrainian authorities have blamed on Russia. At the same time, she noted that Germany hasn’t changed its refusal to provide it with weapons.

"We made clear that we will do everything to avoid escalating the crisis," she said.

German Chancellor Olaf Scholz said on a visit to Spain that "we expect clear steps from Russia to deescalate the situation," and added that "military aggression against Ukraine would entail serious political and economic consequences."

Ukrainian officials have warned that Russia could launch an attack from various directions, including from the territory of its ally Belarus.

Belarusian President Alexander Lukashenko, who has increasingly relied on the Kremlin's support amid Western sanctions over a brutal crackdown on domestic protests, said Russia and Belarus will hold massive military drills next month.

Lukashenko said the maneuvers will be conducted on Belarus' western border and also in the country's south, where it borders Ukraine. Belarus said Tuesday that Russian troops had begun arriving in the country for military drills. The Belarusian Defense Ministry said it was hosting the combat readiness drills because of the continuing "aggravation" of tensions "including at the western and southern borders of the Republic of Belarus."

Russia annexed the Crimean Peninsula from Ukraine in 2014 after the ouster of Ukraine’s Moscow-friendly leader and also threw its weight behind a separatist insurgency in eastern Ukraine. More than 14,000 people have been killed in nearly eight years of fighting there.

Russian President Vladimir Putin has warned that Moscow will take unspecified "military-technical measures" if the West stonewalls its demands.

Deputy Foreign Minister Sergei Ryabkov, who led the Russian delegation at the talks with the U.S. in Geneva, said last week that he would "neither confirm nor exclude" the possibility of Russia sending military assets to Cuba and Venezuela if the U.S. and its allies don’t curtail their military activities on Russia’s doorstep. U.S. national security adviser Jake Sullivan has dismissed the comments as bluster.

Asked Monday about the possibility of Russian missile deployment to Cuba and Venezuela, Kremlin spokesperson Dmitry Peskov told reporters that "Russia is thinking about how to ensure its security in the context of the current situation."