NATO chief Jens Stoltenberg will hold crunch talks with Turkish President Recep Tayyip Erdoğan in the coming weeks over Sweden joining the alliance.
Ankara has so far blocked Stockholm’s bid to join the Western military coalition, accusing the Swedes of harbouring what Turkey claims are militants from the banned Kurdistan Workers’ Party, the PKK.
Arriving in Oslo for a summit of NATO foreign ministers, including British Foreign Secretary James Cleverly, Secretary-General Mr Stoltenberg said he would “travel to Ankara in the near future to continue to address how we can ensure the fastest possible accession of Sweden”.
He added: “Full-fledged membership of NATO is good for Sweden, it’s good for the Nordic countries, for Norway, for the Baltic region - but it’s also good for the whole of NATO.
“This would strengthen NATO and make NATO stronger, and that’s of course also good for Turkey and all other allies.”
Stockholm’s application for membership was triggered by Russia’s invasion of Ukraine.
Coalition chiefs are set to discuss welcoming new members, including Ukraine, when they meet for their annual summit in Lithuanian capital Vilnius next month.
Mr Stoltenberg said Sweden was already on the path to membership and would enjoy defence and security benefits even before its application was approved.
“Sweden, as an invitee to the alliance, is now integrating more and more into NATO structures, our military structures, our civilian structures - and several allies also provided bilateral security assurances for Sweden,” he said.
“It’s absolutely inconceivable that there will be any threat or any attack against Sweden without NATO reacting.”
Britain is one of the countries which struck a deal with Sweden last year guaranteeing its security against Russia.
But Stockholm’s application has stalled amid ongoing tension with the Turks.
Former Norwegian Prime Minister Mr Stoltenberg, who is standing down as head of NATO after nine years, pointed to moves the Swedish government has made which could smooth its passage.
“Sweden is already very close to NATO and Sweden is in a much stronger position after the decision to invite Sweden - and that was a decision also Turkey supported when we made the decision last June,” he said.
“As of today, June 1, new counter-terrorism laws have come into force in Sweden.
“These laws actually make a difference and they demonstrate that Sweden is now taking new steps to step up the fight against terrorism including, for instance, PKK which is a terrorist organisation not only based on the assessment of Ankara and Turkey, but also of Sweden, the European Union and many others.”
Mr Stoltenberg said “Turkey has some legitimate security concerns”, admitting: “No other ally has suffered more terrorist attacks than Turkey.
“Therefore it is important that we work together with Turkey to fight terrorism in all its forms and manifestations.”
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