Swedish bid to join NATO gathers momentum, with governing party backing membership

Magdalena Andersson says Sweden must decide if its military non-alignment is still serving it well. (AP: Fredrik Persson)

Sweden's Prime Minister says the governing Social Democratic party will back a bid to join NATO, hours after Finland formally announced its plans to join the trans-Atlantic military alliance.

Prime Minister Magadalena Andersson said the Kremlin only had itself to blame for Sweden and Finland wanting to join NATO.

"The Kremlin has shown that they are prepared to use violence to achieve their political objectives and that they don't hesitate to take enormous risks," she said in a statement read out in English and referring to Russia's invasion of Ukraine.

"With this in mind, our conclusion is that as a member of NATO, Sweden will not only achieve more security but also contribute to more security."

The plan to join the alliance will be discussed in Sweden's parliament on Monday, and Ms Andersson's cabinet will make an announcement later in the day.

Earlier in the day, Finland's government declared a "new era" was underway after also announcing its intention to seek NATO membership.

Russia has long bristled about NATO moving closer to its borders, so the developments are expected to further anger Moscow.

President Vladimir Putin warned his Finnish counterpart on Saturday that relations would be "negatively affected".

Jens Stoltenberg (centre) holds a media conference with Finland's Foreign Minister Pekka Haavisto (left) and Sweden's Foreign Minister Ann Linde. (AP: Olivier Matthys)

NATO secretary-general Jens Stoltenberg said on Sunday he was confident the accession process for Finland and Sweden could be expedited.

Speaking after top diplomats from the alliance's 30 member states met in Berlin, he said he did not expect Turkey to hold up the process.

Turkey has raised concerns about the two countries joining, alleging they support Kurdish militants that Ankara considers terrorists.

"When an ally raises concerns, we have proven over decades in NATO that we are able to sit down and then find consensus, find a way to agree and then move forward," Mr Stoltenberg told reporters in Berlin.

Mr Stoltenberg also said the alliance would increase its presence in the Baltic region to deter Russian threats.

"All allies realise the historic magnitude of the moment," Mr Stoltenberg added.

ABC/wires