President Joe Biden welcomed Swedish Prime Minister Ulf Kristersson to the White House on Wednesday, just days ahead of this year’s NATO Summit, as Turkey and Hungary continue to object to the Nordic country’s entry into the alliance.

In a show of solidarity, Biden on Wednesday called the prime minister a “valued friend” while continuing to push for Sweden’s accession into the 31-member security alliance.

“Sweden is going to make our Alliance stronger and has the same value set that we have in NATO,” Biden said during brief remarks at the top of the meeting. “And I’m really looking, anxiously looking forward for your membership.”

“We highly appreciate your strong support for Sweden’s NATO accession, that means a lot to us,” Kristersson said to Biden. “We do seek common protection, but we also do think that we have things to contribute.”

Sweden and Finland both applied for NATO membership following Russia’s invasion of Ukraine last year. The moves ended both Nordic nations’ long-standing policy of military nonalignment, potentially due to fear of becoming a target of Moscow. Finland, for instance, shares a more than 800-mile border with Russia.

Turkey and Hungary originally objected to both Finland and Sweden’s bids before signing off on Finland’s and clearing the way for the country to become the alliance’s newest member in April. However, both Turkey and Hungary have kept their opposition to Sweden’s entry.

NATO requires the unanimous approval of all members to expand.

Turkish President Recep Tayyip Erdogan says Sweden is too lenient toward groups that it says pose a security threat, including militant Kurdish organizations and people associated with a 2016 coup attempt in Turkey.

Sweden changed its anti-terror legislation since applying for NATO membership, but Turkey argues supporters of militant groups can freely organize demonstrations, recruit and procure financial resources in the country.

“Turkey has a really expansive, broad definition of what a terrorist is, also with questionable criteria on free speech issues,” fellow at Brookings Institution Aslı Aydıntaşbaş said. “Whereas, Sweden is the other end of the spectrum, they basically allow all types of political activity and activism.”

Matters were only complicated last week after Swedish police allowed a Quran-burning protest outside a mosque in central Stockholm, citing free speech.

“It makes it more or less impossible for Erdogan to sign off on Sweden's membership. What you have is basically a clash of two different worldviews,” Aydıntaşbaş said. “For Erdogan, Quran-burning is not a free speech issue. For the Swedish government, burning the Bible, Quran or anything else is effectively a free speech issue.”

NATO Secretary-General Jens Stoltenberg said he would gather senior officials from Turkey, Sweden and Finland on Thursday to try to overcome Turkey’s objections.  

“[Stoltenberg] has a unique role as an Erdogan whisperer. He's one of the few leaders who can talk to Erdogan,” Aydıntaşbaş said.

Biden is preparing to head to Europe next week for the NATO Summit on July 11-12 in Vilnius, Lithuania. The alliance had hoped the pathway for Sweden’s entry would have been cleared by the annual gathering.

“I think the [Biden] administration is very invested in making this upcoming NATO Summit a success story and really interested in pushing behind the scenes to get a yes for Sweden. That inevitably involves putting things on the table for Erdogan,” Aydıntaşbaş said noting defense sales between the U.S. and Turkey adds layers to the issue.   

In terms of Hungary, Prime Minister Viktor Orban’s government accused Sweden of telling “blatant lies” about Hungary’s democracy. However, high-ranking officials have said they support Sweden’s membership while also making vague demands. Hungarian lawmakers said a delayed parliamentary vote would not happen until the legislative session in the fall.

During their private White House meeting on Wednesday, the two leaders were also expected to discuss security cooperation, Russia’s war in Ukraine and matters involving China. 

The Associated Press contributed to this report.