Moscow -- Russia's high court on Thursday threw out a bid by campaigners to reopen an enquiry into a 1940 massacre of Polish officers by Soviet secret police, an issue still aggravating Polish-Russian ties.

The high court's military chamber left in place "without changes" a lower court ruling that refused to reopen an enquiry into the World War II-era Katyn massacre, Russian news agencies quoted the judge as saying.

The lawyer for relatives of 10 of the Katyn victims, Anna Stavitskaya, said the decision meant the end of efforts by campaigners to resolve the issue in Russia and they would now turn to the European Court of Human Rights in Strasbourg.

"I'm disappointed Russia didn't want to pursue this but I'm glad it's over because it allows us to turn to the European court. I don't see any prospects for pursuing this in Russia," Stavitskaya told AFP.

In 2004, Russia's military prosecutor shut down an enquiry into the massacre of some 22,000 Polish officers that for decades was blamed by Soviet authorities on German Nazi troops but was in fact carried out by Joseph Stalin's secret police.

Earlier, the first post-Soviet president, Boris Yeltsin, had opened up secret files on the case for examination.

But with the shut-down of the enquiry under former president now prime minister Vladimir Putin its contents were again declared secret.

The issue, portrayed in a 2007 film, "Katyn," by the Polish director Andrzej Wajda, has aggravated an often rocky relationship been Russia and Poland, which has urged Russia to recognise the massacre as a crime against humanity.

Campaigners say that under Putin the authorities have been much less willing to examine the horrors of the Soviet past and have harassed research groups such as the respected human rights organisation Memorial.

"If it wasn't for political influences, then it would have been possible for the Russian court to resolve this," commented the head of Memorial, Arseny Roginsky, quoted by Interfax.

In Tuesday's ruling the judge gave a host of reasons for not reopening the enquiry.

These included a statute of limitations in the then Soviet law, the fact that all the perpetrators called to account in the enquiry have died and the failure of the 10 relatives to provide genetic evidence matching them to remains from the Katyn massacre sites.

The thousands of Polish officers were killed in April to May of 1940 in a variety of sites across western Russia and Ukraine, the most prominent being at Katyn forest in western Russia near the city of Smolensk.

It was in 1990 that last Soviet leader Mikhail Gorbachev admitted the Soviets had killed the Polish prisoners as "enemies of Soviet power."

Gorbachev has since supported calls for a full enquiry.

Poland's President Lech Kaczynski visited the massacre site in September 2007 and has repeatedly raised the issue in his presidency.

AFP/Expatica