In a potentially huge foreign policy shift, Sweden will apply for North Atlantic Treaty Organization (NATO) membership in June, according to Swedish daily newspaper Svenska Dagbladet.

Swedish Prime Minister Magdalena Andersson said on Wednesday that she and Finland's Prime Minister Sanna Marin were communicating regularly about possibly joining the defense alliance.

"In order to strengthen our security, discussions are going on in both our countries and Sanna will update me on the Finnish, and I will give her an update on the discussions here in Sweden between the political parties in the Swedish Parliament," Andersson said, per Newsweek. "Even though our respective security choices are independent, it's up to every country to decide for themselves; we do depend on each other in our deep security cooperation."

Marin said previously that Finland will decide whether to apply to become a member of the alliance by the end of spring.

The Swedish newspaper Aftonbladet reports that Andersson’s party, the Social Democrats, has called a meeting on May 24 to discuss NATO membership.

But an unnamed government source reportedly told Svenska Dagbladet that Andersson will submit Sweden’s membership application during the NATO summit in Madrid, Spain, on June 29 and 30.

Until recently, the two Nordic countries felt peace was best maintained by remaining neutral publicly, Reuters reports.

Sweden was neutral during World War II and has not fought a war in more than 200 years.

Citing a March Kantar Sifo poll, Newsweek reports that support for NATO membership among Swedes has grown, with nearly 6 out of 10 in favor of the move if Finland joins.

On Monday, the Kremlin warned Sweden and Finland against joining NATO and said doing so would not bring further stability to Europe.

Kremlin spokesperson Dmitry Peskov told reporters, "We have repeatedly said that the alliance remains a tool geared towards confrontation and its further expansion will not bring stability to the European continent."

With the admittance of Sweden and Finland, NATO would grow to 32 members. Russian President Vladimir Putin has said any further eastward expansion would be considered a direct threat to Russia.

NATO Secretary-General Jens Stoltenberg said that Sweden and Finland would be welcomed into the alliance’s ranks if they seek membership.

"If they decide to apply, I expect that all allies will welcome them," Stoltenberg told reporters in Brussels Wednesday. "We know that they can easily join this alliance if they decide to apply."

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