(Adds Cameron response, opposition Labour quote)
By Kylie MacLellan
LONDON, July 23 (Reuters) - Lawmakers on Wednesday queried why Britain had granted licences to sell tens of millions of pounds worth of arms to Russia, embarrassing Prime Minister David Cameron, who has called for a Europe-wide ban on such sales because of the Ukraine crisis.
The criticism, in a report compiled by four of parliament's select committees, comes two days after the British leader said France's sale of two helicopter carriers to Russia would be "unthinkable" in Britain.
The government said in March it would stop some arms exports to Russia, but the report said that as of mid-May only 34 of 285 outstanding licences, worth more than 131 million pounds ($223.41 million), had been suspended or revoked.
"We should have been applying a more cautious approach for some considerable time towards Russia," said John Stanley, chairman of parliament's Committees on Arms Export Controls.
"Many people ... given the nature of the Russian regime, will be wondering why it is the UK is giving export approval to a particular number of items on that list."
Cameron said he believed the government had been consistent with the existing arms embargo, aimed at Russian military and goods which could be used in Ukraine, but that the government would review the remaining licences.
"We will look very carefully at all outstanding licences and make sure that's the case, and of course if it's not the case we would want to act very swiftly," he told the BBC.
Cameron's spokesman earlier said licences for non-military users, such as hunting enthusiasts, had not been blocked.
In a separate statement, a government spokesman said it had never approved the export of missiles or missile parts to the Russian military, despite suggestions from local media that it had. Nor had it approved licences for the export of rifles or ammunition to the Russian military, he said.
The lawmakers' report covered exports in 2013, before the current ban on arms sales to the Russian military entered into force, the spokesman said.
At odds with the government, lawmakers asked the government to explain why it had approved contracts for everything from body armour to components for assault rifles and military communications equipment.
Cameron has talked tough on Russia following the downing of a Malaysian airliner last week, saying Britain will no longer sell arms to Moscow. He has also said the weight of evidence suggests the plane was shot down by a missile fired from territory in eastern Ukraine held by pro-Russian separatists.
The opposition Labour party questioned the government's willingness to stand up to Russia, however.
"If the government has failed to live up to its pledge on arms sales to Russia, it will raise serious questions about their resolve to now take the steps needed to bring pressure to bear on President Putin," Labour foreign affairs spokesman Douglas Alexander said.
In the same report, lawmakers were also critical of arms sales to Syria, saying the government's decision to approve export licences for chemicals to Syria in January 2012 after the civil war there had started was "irresponsible".
The report also said that a decision by the previous government to approve five export licences for dual-use chemicals to Syria between July 2004 and May 2010 had been "highly questionable".
The government said there was no evidence to suggest that the chemicals were used for anything other than their legitimate end-use and that two of the licences issued in 2012 were revoked before the goods were sent.
($1 = 0.5865 British Pounds) (Editing by Andrew Osborn and Larry King)
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