Turkish President Recep Tayyip Erdogan has said that NATO should not bet on his country approving Sweden's application to join the Western military alliance before a July summit because the Nordic nation has not fully addressed his security concerns.

Sweden and Finland applied for membership together following Russia's invasion of Ukraine last year. Finland became NATO's 31st member in April after the Turkish parliament ratified its request, but Turkey has held off approving Sweden's bid.

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NATO wants to bring Sweden into the fold by the time the leaders of member nations meet for a summit in Lithuania's capital on July 11-12. Speaking to journalists on his way back from a state visit to Azerbaijan on Tuesday, Erdogan said Turkey's attitude to the accession was not "positive."

Turkey's state-run Anadolu Agency and other media reported Erdogan's comments as senior officials from NATO, Sweden, Finland and Turkey met in Ankara on Wednesday. The officials discussed what Finland and Sweden have done to address Turkey's concerns over alleged terrorist organizations.

Erdogan said the Turkish delegation at the meeting "will give this message: 'This is our president's opinion, don't expect anything different at Vilnius,'" Lithuania's capital.

Turkey's government accuses Sweden of being too lenient toward groups that Ankara says pose a security threat, including militant Kurdish groups and people associated with a 2016 coup attempt.

Also read: Erdogan says no support for Sweden's NATO bid

A series of separate demonstrations in Stockholm, including a protest by an anti-Islam activist who burned the Quran outside the Turkish Embassy, also angered Turkish officials.

Speaking in Sweden's parliament, Swedish Prime Minister Ulf Kristersson called the Ankara meeting "very important." Kristersson reiterated that his government had done what it promised in an agreement last year that was intended to secure Turkey's ratification of the country's NATO membership.

However, Erdogan remained unsatisfied. He said he told NATO Secretary-General Jens Stoltenberg last week, "If you expect us to respond to Sweden's expectations, first of all, Sweden must destroy what this terrorist organization has done." He was referring to the Kurdistan Workers' Party, or PKK, a group that has waged a separatist insurgency in Turkey.

Erdogan said that pro-Kurdish and anti-NATO rallies also took place in Stockholm during his meeting with with Stoltenberg in Istanbul.

A statement issued by the Turkish presidency after Wednesday's said the parties "held consultations on the activities of terrorist groups in Sweden based on concrete examples." It said they agreed to continue working on further steps.

Also read: Erdogan might approve Finland’s NATO bid, ‘shock’ Sweden

Stoltenberg said his chief of staff, who attended the meeting, reported that it took place in a "constructive atmosphere."

"Some progress has been made, and we will continue to work for the ratification of Sweden as soon as possible," he said.

Asked whether NATO would be able to admit Sweden before the Vilnius summit, Stoltenberg replied, "It is still possible. I cannot guarantee it, of course."

NATO requires the unanimous approval of all existing members to expand, and Turkey and Hungary are the only countries that have not yet ratified Sweden's request to join. Erdogan said he planned to attend the July summit in Lithuania unless "extraordinary" circumstances arise.

On Tuesday, U.S. Secretary of State Antony Blinken said after meeting with Stoltenberg that it was "time to welcome Sweden" into the alliance, arguing that Stockholm had "an important and I think very appropriate process on its accession to address appropriate concerns of other allies."

Sweden has amended its constitution and strengthened its anti-terror laws since it applied to join NATO just over a year ago. This week, the Swedish government also decided to extradite a Turkish citizen resident in Sweden who was convicted for drug offenses in Turkey in 2013.

Sweden and Finland applied to become NATO members in the wake of Russia's invasion of Ukraine, abandoning decades of nonalignment.