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Finland’s president launched a stinging attack on Russia, saying “you caused this”, in reference to his country being on the cusp of joining Nato.
During a day of significant developments in the growing alliance against Russian aggression, Britain signed a mutual defence pact with both Sweden and Finland.
Both Nordic countries are now on the verge of joining the Nato alliance, a move that is likely to both infuriate President Vladimir Putin and lead to retaliation from Moscow.
During a press conference in Helsinki on Wednesday announcing the new military alliance with Britain, Sauli Niinisto responded to a question on why Finland would join the alliance and potentially inflame relations with its neighbour.
Standing next to Boris Johnson, Mr Niinisto said his country would be threatened by Russia with “contra steps”, having been told by Mr Putin last year not to join Nato.
“By stating that, Russia stated we don’t have our own will — that made a huge change,” he said and added that Moscow was now “ready to attack a neighbouring country” following the invasion of Ukraine.
Visibly angry, he then stated: “My response is that you caused this. Look in the mirror.”
The National reported on Wednesday that people in Sweden were preparing emergency provisions in the event of a Russian cyber strike that could affect the country's electricity. Finland, too, is on high alert, with preparations being made to ready thousands of bunkers that can shelter four million people from the fallout from a nuclear attack.
The new defence agreement with Britain will also help with security in the period between applying for Nato membership and joining — potentially six month later — without being covered by the mutual aid pact of the Article Five collective defence obligation.
Shortly after signing the agreement, Mr Johnson said it “made clear something that needs to be made clear in the context of today”.
“This is a pledge that we will always come to one another’s aid … if anyone is attacked, we will come to each other’s assistance,” he added.
Mr Niinisto is expected to formally announce on Thursday that his country will seek to join Nato.
“For us, joining Nato is not against anybody — we want to maximise our security,” he said speaking at the press conference in Helsinki’s presidential palace.
During a day-long tour of the two Nordic states, the British prime minister arrived first in Stockholm where he signed the agreement with his Swedish counterpart, Magdalena Andersson
“We are steadfast and unequivocal in our support to both Sweden and Finland and the signing of these security declarations is a symbol of the everlasting assurance between our nations,” he said.
“These are not a short-term stopgap but a long-term commitment to bolster military ties and global stability and fortify Europe's defences for generations to come.”
Both Sweden and Finland will now expect to see British and US troops stationed in their countries in the coming months at least until their applications are approved by all 30 Nato member states.