US President Joe Biden has signed documents endorsing Finland and Sweden’s accession to NATO alliance.

Celebrating the US decision to ratify both the countries, President Biden said, their alliance is closer than ever, it is more united than ever, and after Finland and Sweden join they will be stronger than ever.

Sweden and Finland applied for NATO membership in response to Russia’s militay actions in Ukraine. Moscow has repeatedly warned both countries against joining the alliance.

Last week, the Senate voted 95 to 1 to ratify the entrance of Finland and Sweden into the world’s most powerful military alliance. Both Finland and Sweden already meet many of the requirements to be NATO members.

NATO’s 30 allies signed the accession protocol for Sweden and Finland last month, allowing them to join the nuclear-armed alliance once all member states ratify the decision.