HELSINKI • The government has announced plans to boost Finland's military capacity because of concerns over the assertive behaviour of its powerful neighbour Russia.

Finland, which is not a Nato member, will increase the number of its wartime troops from 230,000 currently to 280,000, to "improve the capability to defend the entire territory of the country", which shares a 1,340km border with Russia, the government wrote in a defence report.

"Russia aims to strengthen its great-power status, and it has expressed the goal of a sphere-of-influence-based security regime," the report said, noting that the security situation in the Baltic Sea region surrounding Finland had deteriorated.

"The early-warning period for military crises has become shorter and the threshold for using force has lowered (in the region)," the report stated.

The increase in wartime troops entails a modest addition of €55 million (S$83 million) to Finland's annual military spending of €2.9 billion. The government said that expenditure would increase more significantly after 2020.

Finland is preparing to replace its 62 F/A-18 Hornet jets with multi-role fighter aircraft in a procurement estimated to cost between €7 billion and €10 billion, but the final decision is not expected until the next decade.

In October last year, Finland and the United States signed a bilateral defence cooperation deal, after a similar agreement between Sweden and the US was inked in June.

Since Russia's annexation of Crimea in 2014 and the conflict in eastern Ukraine, Finland has also stepped up bilateral military cooperation with Sweden, its western neighbour.

AGENCE FRANCE-PRESSE, REUTERS