The British Parliament is set to decide whether to take more aggressive action against Islamic State extremists by launching airstrikes inside Syria.

The vote expected Wednesday evening would authorize bombing inside Syria. Britain has been participating in U.S.-led coalition attacks against IS positions in Iraq only.

Prime Minister David Cameron argues that expanding the airstrikes would strengthen Britain's security by degrading the IS forces responsible for recent attacks in Paris, Beirut and elsewhere. Cameron has said he wouldn't seek Parliament's backing unless he was confident of getting it.

Opposition Labour Party leader Jeremy Corbyn accuses Cameron of leading a rush to war, but several dozen Labour legislators are expected to support airstrikes.

Attacks may start within days if authorized by Parliament, which defeated a similar measure two years ago.