<b>Live updates: follow the latest news on </b><a href="https://www.thenationalnews.com/world/2022/02/18/russia-ukraine-latest-news/"><b>Russia-Ukraine</b></a> UK Prime Minster Boris Johnson will sign historic security assurance declarations with <a href="https://www.thenationalnews.com/world/europe/2022/05/09/sweden-and-finlands-nato-membership-boosts-natos/" target="_blank">Sweden </a>and <a href="https://www.thenationalnews.com/world/uk-news/2022/05/03/nato-urged-to-close-weapons-gap-with-new-system-for-supplying-arms-to-ukraine/" target="_blank">Finland </a>in the face of <a href="https://www.thenationalnews.com/world/uk-news/2022/05/11/battle-for-ukraines-snake-island-key-to-black-sea-dominance/" target="_blank">Russia's invasion of Ukraine</a>, pledging to “bolster military ties” and support both countries should they come under attack. The prime minister arrived in Stockholm on Wednesday before travelling to Harpsund, the rural residence of his Swedish counterpart Magdalena Andersson, where he set out a UK commitment to come to the country's aid in the event of a crisis. “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,” Mr Johnson 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.” Mr Johnson is set to visit Finland later on Wednesday, where he is expected to formalise a similar agreement with the country's President Sauli Niinisto during a whirlwind 24 hours. He will also offer to send more military assistance to the region, including Royal Air Force, British Army and Royal Navy personnel and assets. It comes as Finland and Sweden consider the prospect of Nato membership in the face of Russian President Vladimir Putin's continuing military aggression in Ukraine. Sweden has launched preparations for hostilities with Russia immediately after its Nato application, with families <a href="https://www.thenationalnews.com/world/europe/2022/05/11/sweden-stockpiles-against-possible-russia-attack-over-nato-application/" target="_blank">stocking up on provisions</a> in case of an attack, <i>The National</i> has learnt. The declarations build on claims made this month that the UK would always aid Finland if it were attacked by Russia, regardless of whether the country was a member of Nato. Defence Secretary Ben Wallace said it was “inconceivable” that Britain would not help either Finland or Sweden if it were in crisis, even “without any big formal agreement”. Mr Johnson held talks with Ms Andersson and Mr Niinisto in March as part of a meeting of the Joint Expeditionary Force nations, which includes Denmark, Estonia, Iceland, Latvia, Lithuania, the Netherlands and Norway. After the meeting, No 10 Downing Street said the two leaders agreed that “Putin's invasion had dramatically changed the landscape of European security”. Finland shares a lengthy land border with Russia and is only about 250 miles from St Petersburg.