(Adds comments, background)
HELSINKI, Nov 29 (Reuters) - The U.S. State Department has approved a second significant arms sale to Finland within a month, helping Russia's Nordic neighbour in its bid to strengthen its defences due to the war in Ukraine, Finland and the United States said.
After Russia invaded Ukraine in February, Finland's government decided to grant an additional 1.7 billion euros ($1.76 billion) to arms and other defence material purchases this year alone.
"A very significant share of it will go to (purchases) from the U.S.," Governmental Counsellor Iikka Marttila from Finland's Defence Ministry said on Tuesday.
The State Department said the proposed sale of AIM 9X Block II tactical missiles, AGM-154 Joint Stand Off weapons and related equipment, for an estimated $323.3 million, would improve Finland’s air-to-air and air-to-surface weapons capabilities.
Finland plans to use the missiles with its new fleet of F-35 stealth jets it is also buying from the United States.
Earlier this month, the State Department also approved the sale of 150 Guided Multiple Launch Rocket Systems and related equipment for an estimated cost of $535 million.
Finland has been building its own defence capabilities for decades but after Russia initiated its "special military operation" in Ukraine, Finland applied to join the Western military alliance NATO in a security policy U-turn together with neighbouring Sweden.
The U.S. sales approvals come at a time when there is high international demand and competition for arms systems due to the war, Marttila said.
"Of course we stress our own position as Russia's neighbour and seek to influence in the way that we could purchase these as quickly as possible," he told Reuters, adding the latest purchases would be approved by the ministry early next year. ($1 = 0.9635 euros) (Reporting by Anne Kauranen, Editing by Andrew Heavens and Alison Williams)