Sweden on Tuesday expressed its willingness to expand cooperation with Turkey within NATO amid Ankara's objections to the Scandinavian country's membership application to the bloc.

Finland and Sweden have officially submitted their membership bids to join the NATO military alliance. Turkey, a longstanding NATO member, has voiced its objections to Finland and Sweden's membership bids, criticizing the two Nordic countries for tolerating and even supporting terrorist groups like the PKK, its Syrian branch, the YPG, and the Gülenist Terror Group (FETÖ).

Speaking at a news conference with Finland's President Sauli Niinisto in Stockholm, Swedish Prime Minister Magdalena Andersson said Sweden cares about negotiating with Turkey on her country's bid for NATO membership.

"Like NATO and the EU, Sweden also stands for fighting all forms of terrorism," she said, adding that they are ready for dialogue with Turkey "to discuss and resolve existing question marks."

Saying that she is ready to pay a visit to Turkey regarding the issue, Andersson confirmed that Finland and Sweden are to submit their bids to join the military alliance together on Wednesday at NATO headquarters in Brussels.

For his part, Niinisto said he was surprised over Turkey opposing Finland and Sweden's NATO membership and voiced readiness for negotiations with Ankara.

Turkey's reservations on Finland and Sweden's NATO membership bids can be resolved with the help of constructive talks, said Finland's president.

Speaking in the Swedish parliament, the Rigksdag, Niinisto said: "The statements from Turkey have changed and hardened very quickly in recent days."

He added: "But I am sure that, with the help of constructive talks, we will resolve the situation."

President Recep Tayyip Erdoğan on Monday reiterated Turkey’s objections and said the country will not approve Sweden and Finland’s bid to join NATO, as he criticized them for failing to take a clear stance against terrorist organizations.

Turkey last week said it would not view their applications positively, mainly citing their history of support to terrorist organizations, including the PKK and its Syrian wing, the YPG.

Any membership bid must be unanimously approved by NATO’s 30 members.

"Neither of these countries has a clear, open attitude toward terrorist organizations," Erdoğan said at a joint news conference with his Algerian counterpart Abdelmadjid Tebboune in the capital Ankara. "How can we trust them?"

"First of all, we cannot say ‘yes’ to those who impose sanctions on Turkey, on joining NATO which is a security organization," he noted.

Sweden and Finland had imposed arms export embargoes on Turkey after its military operation seeking to clear northern Syria, east of the Euphrates, of the YPG in 2019.

Erdoğan described Sweden as an "incubation center for terrorist organizations," saying some members of its parliament supported the PKK, designated as a terrorist organization by Turkey, the United States and the European Union.

The Swedish foreign office said earlier on Monday that senior representatives of Sweden and Finland plan to travel to Turkey for talks to address Ankara’s concerns.

However, Erdoğan said they "should not bother" coming if they hope to convince Ankara into relaxing its objections to their membership.

"They say they will come to Turkey on Monday. Are they coming to convince us? Excuse me but they should not tire themselves," he noted.

Erdoğan said NATO would become "a place where representatives of terrorist organizations are concentrated" if the two countries joined.

The president said Sweden and Finland rejected to extradite people with links to the PKK and FETÖ, the terrorist group behind the defeated coup of 2016 in Turkey.

The Justice Ministry on Monday said the two countries had not granted approval to Turkey’s request for the extradition of 33 people with links to the PKK and the FETÖ.

Turkey said it wanted the Nordic countries to halt their support to terrorist groups present on their territory, and lift bans on sales of some weapons to Turkey.

As Bloomberg reported citing senior Turkish officials who did not reveal their names, Ankara offers many conditions, including the lifting of arms embargoes, a return to the F-35 program, and the recognition of the PKK as a 'terrorist organization' by the two countries.

Turkey has been requesting a return for its $1.4 billion (TL 22.3 billion) investment in the U.S.-led multinational fifth-generation F-35 fighter jet program, from which it was removed by Washington in 2019 after it acquired S-400 missile defense systems from Russia. Ankara had ordered more than 100 F-35 jets, made by Lockheed Martin, while its defense industry has been a prominent player in the development and manufacturing of fighter jets.

Washington argues that the S-400 air missile systems acquired by Turkey could be used by Russia to covertly obtain classified details on the F-35 jets and that they are incompatible with NATO systems. Turkey, however, insists that the S-400 would not be integrated into NATO systems and would not pose a threat to the alliance. Ankara has reiterated on various occasions that its removal from the jet program was illegal and unilateral. It has demanded a fair approach and has said that it is open to negotiations with Washington.

Western countries and organizations try to convince Turkey to support the bid after Erdoğan's statements.

"It is not for us to speak for the Turkish government," State Department spokesperson Ned Price said repeatedly on Tuesday in response to multiple questions about what the U.S. understands Turkey’s position to be and whether Turkey had demanded anything from the United States in return for agreeing to Finland's and Sweden’s memberships.

Moscow’s invasion of Ukraine on Feb. 24 has swung political and public opinion in Finland and neighboring Sweden in favor of NATO membership as a deterrent against Russian aggression.

Sweden and Finland were both neutral throughout the Cold War, and their decision to join NATO would be one of the biggest changes to Europe’s security architecture for decades, reflecting a sweeping shift in public opinion in the Nordic region since Russia invaded its neighbor Ukraine in February.

Moscow has responded to the prospect of the Nordic states joining NATO by threatening retaliation, including unspecified "military-technical measures."