Denmark said Thursday that it would join a Britain-US coalition that has carried out airstrikes against Iran-backed Houthi rebels in Yemen who are behind a recent spate of attacks on ships in the Red Sea.

The Houthis say their attacks are in support of Palestinians in the Israel-Hamas war in Gaza.

Washington and London have launched a series of strikes against Houthi positions to bring an end to the attacks that have caused shipping companies to bypass the Red Sea, significantly adding to journey times and cost.

"We have responded to the request for Denmark to take part in the coalition," Defence Minister Troels Lund Poulsen told reporters.

He said Denmark would contribute an officer from its general staff who would take part in planning operations.

"This is a serious situation, one in which Denmark says it will also take political responsibility to bring an end to what is going on," Poulsen said.

The Scandinavian country, which has previously said it would send a frigate to the region, is home to shipping giant Maersk, which has rerouted its ships away from the Red Sea.

In December, the Pentagon said 20 countries had joined the Washington-led coalition to protect the key shipping lane. (AFP)