There are strong indications that Russian President Vladimir Putin decided to supply the missile that downed flight MH17 in 2014, international investigators say.

The aircraft was hit by a Russian-made missile over Ukraine, killing nearly 300 people.

Prosecutors said there was evidence that Mr Putin decided to provide the missile to Moscow-backed separatists.

There is no suggestion that Mr Putin ordered the aircraft be shot down.

Russia denies all involvement in the downing of the plane.

The prosecutors said on Wednesday that they had exhausted all leads and could not continue with any more criminal proceedings.

The Boeing 777 was flying from the Dutch capital to Kuala Lumpur when it was hit by a Russian-made surface-to-air missile in July 2014 during a conflict between pro-Russia rebels and Ukrainian forces in the Donbas region of Ukraine.

Of the 298 passengers and crew, 196 were Dutch while many of the other passengers came from Malaysia, Australia, the UK, Belgium and other countries.

In a statement, the Joint Investigation Team said the court ruled that Moscow had "overall control" over the Donetsk People's Republic, which controlled the area in July 2014.

It cited recorded telephone conversations where Russian officials said that the decision to provide military support "rests with the President".

"There is concrete information that the separatists' request was presented to the president, and that this request was granted," it said.

But it adds that is not known whether the request "explicitly mentions" the system used to shoot down MH17.

"Although we speak of strong indications, the high bar of complete and conclusive evidence is not reached," investigators said.

"Furthermore, the President enjoys immunity in his position as Head of State."