Sweden has signed a formal request to join NATO, a day after the country announced it would seek membership in the 30-member military alliance.
In neighbouring Finland, lawmakers are expected later in the day on Tuesday to formally endorse Finnish leaders' decision to also join.
The moves by the two Nordic countries, ending Sweden's more than 200 years of military nonalignment and Finland's nonalignment after World War II, have provoked the ire of the Kremlin.
While most NATO members are keen to welcome the two countries as quickly as possible, Turkey has potentially complicated their accession by saying it cannot allow them to become members because of their perceived inaction against exiled Kurdish militants.
Turkish President Recep Tayyip Erdogan on Monday doubled down on comments last week indicating that the two Nordic countries' path to NATO would be anything but smooth.
All 30 current NATO countries must agree to open the door to new members. He accused the two Nordic countries of refusing to extradite "terrorists" wanted by his country.
In Stockholm, Swedish Foreign Minister Ann Linde signed the formal request to join the Alliance, which she said would be sent to NATO Secretary-General Jens Stoltenberg.
"It feels like we have taken a decision that is the best for Sweden," she said while signing the document.
Finnish President Sauli Niinisto arrived in Sweden for an official visit and was welcomed by Sweden's King Carl XVI Gustaf and Queen Silvia, who had invited him. Niinisto is scheduled to address Sweden's Parliament in a speech expected to focus on NATO, and meet Prime Minister Magdalena Andersson.
On Twitter, Niinisto said that "the timing is excellent, a strong and stable Nordic region is our common cause".
Australian Associated Press
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