Sweden's path to NATO membership remains blocked by Türkiye and Hungary ahead of a July summit in Vilnius where it hopes to join Nordic neighbor Finland as a full member of the alliance.

Finland, which applied together with Sweden, joined NATO in April, but Türkiye continues to block Swedish membership citing security concerns. Ankara has said Sweden must crack down on anti-Türkiye protests before getting a green light to join NATO.

Sweden has set its sights on joining at the alliance's July 11-12 summit and while it has strong support from other members including the U.S. and more talks with Türkiye are expected, there have been few clear signs of a breakthrough.

What's the background to the story?

Russia's attack on Ukraine in February last year convinced Sweden and Finland to ditch long-held policies of military non-alignment. Both countries see NATO, with its collective defense clause, as the best way to ensure their security.

The majority of NATO members quickly ratified the applications, arguing that Finland – which shares a 1,300-kilometer border with Russia – and Sweden would strengthen the alliance in the Baltic. However, ratification of NATO membership has to be unanimous – but Türkiye and Hungary have been slow to agree. 

Türkiye gave approval for Finnish membership after initial objections. But Ankara says Sweden does not take its security concerns seriously and has not lived up to a bargain, struck in Madrid last year, that laid out a number of issues Stockholm needed to address.

Türkiye has not budged despite Sweden implementing new anti-terror legislation in June that it believes should pave the way for accession.

Hungary has followed Türkiye's lead in delaying ratification, withholding approval for Finland until March 2023 and to date not yet rubber-stamping Sweden.  

Why does Türkiye object?

Stockholm has criticized Türkiye for human rights abuses and over democratic standards, irking politicians in Ankara.

Türkiye says Sweden harbors members of what it considers terrorist groups – a charge Sweden denies – and has demanded their extradition as a step toward ratifying Swedish membership. Swedish courts have blocked some expulsions to Türkiye.

Demonstrations held in Sweden have also raised Turkish ire. In recent months, demonstrators in Stockholm have hung an effigy of Erdogan from a lamp-post. At other events, demonstrators waved flags showing support for the Kurdistan Workers' Party (PKK), which is deemed a terrorist group by Türkiye and its Western allies, including Sweden.

Swedish Foreign Minister Tobias Billstrom has said the freedom to demonstrate is enshrined in the constitution while adding that "something that is legal is not always proper."

What is Hungary's beef with Sweden? 

Hungary says Sweden has had a hostile attitude to Budapest for years. It is angry about Swedish criticism of Prime Minister Viktor Orban over the perceived erosion of rule of law. Orban denies such erosion. 

Unlike Türkiye, Hungary does not have a list of demands, but says grievances need to be addressed before it can ratify Sweden's accession to NATO.

Swedish officials say they are perplexed by Hungary's stance and analysts have said the country is likely to follow Türkiye's lead in the matter.

When will Türkiye agree to Swedish NATO membership?

Foreign minister Billstrom has been busy meeting a host of NATO allies in recent weeks to ensure Stockholm's membership bid remains top of the agenda, saying there is no "Plan B" beyond Sweden joining in Vilnius.

Sweden says it has implemented the Madrid agreement – including tougher anti-terrorism laws – and that some of Ankara's other demands are impossible to meet.

Erdogan has said the new laws are meaningless while supporters of the outlawed PKK are allowed to hold protests in Stockholm.

Yet Türkiye has had previous run-ins with NATO allies and backed down. Elsewhere, support for Sweden is strong, with leaders from around Europe and the United States calling on Ankara to move ahead with ratification.

Swedish and Turkish officials met on June 14 for what Sweden's chief negotiator characterized as good talks, and are due to hold another high-level meeting in Brussels before the Vilnius summit – a meeting which NATO Secretary-General Jens Stoltenberg hopes will help to seal the deal.

"This meeting will include foreign ministers, heads of intelligence and national security advisers. The aim is to make progress in completing Sweden's accession to NATO," he told reporters during a visit to Vilnius.

Is Sweden's security threatened by the delay? 

Sweden has said its security position is better now than prior to its application to NATO. Sweden has received assurances of support from countries including the United States, Britain and Germany.

Stoltenberg has said it would be inconceivable that the alliance would not support Sweden if it were threatened.

Sweden already cooperates closely with NATO and integration measures are moving forward. Sweden has a strong air force and a submarine fleet tailored to Baltic Sea conditions – a boost for NATO in the region.

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