Nordic air force exercises simulating a UN peacekeeping mission got underway in Sweden's sub-Arctic north on Monday, the Swedish armed forces said.

The war games -- involving 115 fighter planes and 3,600 troops from nine countries -- are being held under the auspices of Nordic military cooperation between non-aligned Sweden and Finland and their NATO neighbour Norway.

Joining the Nordic nations were troops and planes from the US, Britain, Germany, France and the Netherlands -- all Nato members -- as well as neutral Switzerland -- using bases in the far north of Sweden, Norway and Finland.

"I'm looking forward to exercises that prepare Sweden's and Europe's airforces for future challenges and missions," Colonel Carl-Johan Edstroem, head of Sweden's northern air force fleet, said in a statement at the launch of the Arctic Challenge Exercise (ACE).

"We create our security together with others and that means we need to train," he added.

Similar exercises involving fewer countries were held in 2013.

The manoeuvres come at a time of heightened tension in the region as Nordic countries report increased Russian airforce activity close to their borders.

In April all five Nordic defence ministers published an op-ed article in a Norwegian daily announcing closer military cooperation.

"The Russian military are acting in a challenging way along our borders," they wrote, adding that "we must be prepared to face possible crises or incidents."

The exercises continue until June 4 and will be followed on June 5 by NATOs annual Baltops (Baltic Operations)manoeuvres with 4,500 troops from 17 countries.

"These kind of activities send a security policy signal that demonstrate that we can carry out advanced operations," said Swedish Major General Karl Engelbrektson in a statement.

"At the same time we're showing solidarity towards the other participants, especially our nearest neighbours."