Denmark will send seven F-16 fighter jets to help combat IS militants in Iraq, Prime Minister Helle Thorning-Schmidt said on Friday.

"I am very pleased that there now is a broad coalition, including countries in the region who want to... contribute," she said at a press conference, adding that the Danish fighter jets would not join US planes in bombing targets in Syria.

The decision to take part in the campaign in Iraq is expected to receive the support of a majority in parliament and the F-16s could be dispatched next week.

"We were asked to contribute in Iraq, it fits well with what the coalition wants. With regards to Iraq we have a concrete request from the Iraqi government," Thorning-Schmidt said.

"The terror group IS is a terrible organisation that Denmark should help battle," she added.

A US-led alliance launched fresh air strikes against IS in Syria on Friday as Britain weighed joining the aerial campaign in Iraq.

Both France and Britain have ruled out carrying strikes in Syria, unlike Arab allies taking part in the raids.

Belgium and the Netherlands also plan to send six F-16 fighter bombers to take part in the campaign in Iraq.

In August, Danish lawmakers approved sending a C-130J transport aircraft to Iraq and up to 55 military personnel to help load and guard it.