Brussels (AFP) - Belgium's parliament overwhelmingly approved plans on Friday to send six F-16 fighter jets to join the US-led coalition against the Islamic State militant group.

After the vote, the Belgian government said the fighter jets had taken off for Jordan, where they could begin fighting missions over Iraq as early as Saturday.

The deployment follows a formal request from Washington earlier in the week, but will be limited to Iraq.

The threat posed by the IS group prompted the United States to launch airstrikes last month and on Tuesday the operation was expanded to IS and other groups in Syria.

The ratification closely followed a similar vote in Britain, where MPs voted overwhelmingly in favour of committing British forces to join the air strikes.

Denmark and the Netherlands have also announced plans to send fighter jets to help combat IS militants.

Belgium's F-16s will be based in Jordan, one of the Arab nations that has joined the coalition, and are to be accompanied by around 120 personnel, the defence ministry said.

Belgium has expressed mounting concerns over the Islamic State group, with around 350 to 400 of its nationals having gone to fight in Iraq and Syria.