Ukrainian leader Volodymyr Zelenskyy said Wednesday he saw no evidence of a Russian troop withdrawal from his country's borders, saying Moscow was simply rotating forces.
"We are seeing small rotations. I would not call these rotations the withdrawal of forces by Russia. We cannot say that," he said in televised comments.
"We see no change."
Zelenskyy also vowed that his country would stand tall against any invasion, as NATO warned it could see no sign that Russia is withdrawing its forces.
The president watched troops training with some of their new Western-supplied anti-tank weapons on a range near Rivne, west of the capital.
Then he traveled to the frontline port city of Mariupol and gave a speech to mark what he had declared Ukraine's "Day of Unity," wearing a military-style olive green coat and vowing resistance.
"We are not afraid of forecasts, we are not afraid of anyone, of any enemies," Zelenskyy said. "We will defend ourselves."
"We have a wonderful, strong armed forces," he said. "We have excellent diplomats, volunteer forces and national resistance forces throughout Ukraine.
"The strength to protect us. Protect your land. Enough force to not succumb to any provocations."
The demonstration of Ukrainian firepower and rhetoric contrasted with images on Russian state media that were said to show Moscow's forces bringing an end to a major exercise in occupied Crimea.
In Rivne, missiles pounded targets and armored vehicles maneuvered and fired on the yellowing moorland, while in Kyiv hundreds of civilians marched in a stadium with an enormous national banner.
The "Day of Unity" displays came as the Kremlin called for "serious negotiations" with Washington, and European leaders pushed hard for a diplomatic resolution to the crisis.
But NATO chief Jens Stoltenberg, who hosted a meeting of the alliance's defense ministers in Brussels, dismissed suggestions that the threat on the border had diminished.
He said the alliance would shore up its eastern defenses with forward deployments in member states bordering Ukraine.
"Moscow has made it clear that it is prepared to contest the fundamental principles that have underpinned our security for decades and to do so by using force," he said.
"I regret to say that this is the new normal in Europe."
On reported Russian troop movements, he said: "So far we do not see any sign of de-escalation on the ground; no withdrawals of troops or equipment."
"Russia maintains a massive invasion force ready to attack with high-end capabilities from Crimea to Belarus."
Meanwhile, U.S. Secretary of State Antony Blinken told ABC News: "What we're seeing is no meaningful pullback."
Russia's huge buildup of troops, missiles and warships around Ukraine is being billed as Europe's worst security crisis since the Cold War.
Russian President Vladimir Putin has demanded Ukraine be forbidden from pursuing its ambition to join NATO and wants to redraw the security map of eastern Europe, rolling back Western influence.
But, backed by a threat of crippling U.S. and European Union economic sanctions, Western leaders are pushing for a negotiated settlement, and Moscow has signaled it will start to pull forces back.
In the latest such move, on Wednesday the Russian Defense Ministry said military drills in Crimea – a Ukrainian region Moscow annexed in 2014 – had ended and that troops were returning to their garrisons.
Washington has demanded more verifiable evidence of de-escalation, but U.S. President Joe Biden has nevertheless vowed to push for a diplomatic solution.
Kremlin spokesperson Dmitry Peskov welcomed this, telling reporters: "It is positive that the U.S. president is also noting his readiness to start serious negotiations."
German Defense Minister Christine Lambrecht, arriving at the NATO talks, said reports of a partial Russian pullback "are signals that at least give us hope. But it is important to observe closely whether these words are followed by deeds."
EU leaders, already gathered in Brussels for a summit with their African counterparts, are now to hold impromptu crisis talks on Russia and Ukraine on Thursday.
Zelenskyy has downplayed threats of an immediate Russian invasion but is attempting to rally his people with the "Day of Unity" celebrations under Ukraine's blue and gold banner.
On Wednesday, after the Rivne drills, he visited Mariupol, a frontline port city near a breakaway region held by Russian-backed separatists.
The European Union ambassador to Ukraine, Matti Maasikas, along with the German, Estonian, Polish and Spanish envoys headed to Mariupol with the president in solidarity.
Maasikas also said that he had raised the Ukrainian flag alongside the EU one at his embassy, adding: "Not sure it's fully according to the rules, but these are extraordinary times."
In another sign of Ukraine's most powerful figures coming together, some wealthy business leaders who had been urged to come back to the country announced their return.
Ukraine's richest man, 55-year-old billionaire industrialist Rinat Akmetov, who was born in Donetsk in an area now held by separatists, was in Mariupol.
"We continue to build, we continue to invest," he said, promising his firm would boost salaries and support a local university.
On Tuesday, Ukraine said the websites of the country's Defense Ministry, armed forces and two banks had been hit by a cyberattack of the kind that U.S. intelligence fears would precede a Russian attack.
"It cannot be excluded that the aggressor is resorting to dirty tricks," Ukraine's communications watchdog said, in reference to Russia.
Peskov denied that Moscow had any role in the cyber assault. "We do not know anything. As expected, Ukraine continues blaming Russia for everything," he said.