Russian aviation officials say they have uncovered new evidence about the 2014 downing of a Malaysian jet over eastern Ukraine and are asking Dutch investigators to look into the findings.

The Dutch Safety Board said in its final report released in October that Malaysia Airlines Flight 17 was destroyed by a Soviet-made Buk surface-to-air missile.

Moscow has been anxious to deflect suspicion from the rebels it is backing in eastern Ukraine who said before the crash they had this type of missiles.

In a letter to the Dutch Safety Board chairman published on Thursday, the Russian Aviation Agency said its experts have since conducted experiments and research that proved the Dutch probe and its conclusions to be "unsubstantiated and inaccurate."