MOSCOW, Oct 17 (Reuters) - Russian President Vladimir Putin has revoked an additional protocol to the Geneva Conventions related to the protection of victims of international armed conflicts, a Russian parliamentary website cites a letter from him as saying.

The Additional Protocol I to the 1949 Geneva Convention was ratified by the Soviet Union's Supreme Council, or parliament, in 1989.

Putin's letter, dated Oct. 16 and addressed to the speaker of lower house of parliament on the "recall of the statement made at the ratification", said an international commission, set up in order to investigate war crimes against civilians, "has effectively failed to carry out its functions since 1991".

"In the current international environment, the risks of the commission's power abuse by the states, which are acting in bad faith, are increasing significantly," says the document cited by the website that documents laws proposed and passed by the Russian parliament.

It also said that there was no Russian representative on the commission, while Russia has been regularly paying its fees.

It gave no further details about what prompted the decision.

Russia has been accused by critics of causing multiple civilian deaths since its involvement in the Syrian conflict. It was also blamed for killings of civilians during its short war with Georgia in 2008. Moscow denies the allegations.

It is still a signatory to the Geneva Conventions, which is made up of four of treaties and three additional protocols. (Reporting by Vladimir Soldatkin; Editing by Alison Williams)