Turkey will not formally approve Finland and Sweden's membership of NATO until the two countries take the necessary "steps", Turkish President Recep Tayyip Erdogan told alliance chief Jens Stoltenberg Friday.
Erdogan and Stoltenberg held a private meeting in Istanbul that was closed to the media.
Finland and Sweden dropped decades of military non-alignment and scrambled to become NATO members in May, after Russia invaded Ukraine.
But Erdogan threatened to block their bids and sought concessions, leading to a deal in June between Turkey, Finland and Sweden that included provisions on extraditions and sharing information.
New Swedish Prime Minister Ulf Kristersson will visit Ankara on Tuesday to meet with Erdogan in a trip that Stockholm hopes will lead to Turkey's approval.
Stoltenberg "welcomed the major, concrete steps already taken by both countries to put the memorandum into practice, and stressed that their accession will make NATO stronger", the alliance said in a statement on Friday.
New members to the alliance require unanimous approval.
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