Yemen air strikes
People search the rubble at the site of an air strike at a residential area near Sanaa AirportKhaled Abdullah Ali/Reuters

Britain has backed the Saudi Arabia-led campaign in Yemen which has already seen air strikes batter Sana'a and Houthi-held areas of the the country's north.

A foreign office spokesman said in a statement that President Abdrabbuh Mansour Hadi was "the legitimate president of Yemen" and it supported military intervention led by Saudi Arabia and its allies, including the UAE, Qatar, Egypt, Sudan, Turkey, Jordan, Pakistan and Morrocco.

Egypt and Sudan have both announced that they could contribute ground forces to any further operation in Yemen. Samih Shoukri, Egypt's foreign minister, told an Arab League conference in Sharm al-Sheikh that Cairo was willing "to send ground forces if necessary".

The Sunni grand alliance is being called Operation Decisive Storm and has already seen an attack on Sana'a airport and a military airbase close by, Reuters reported.

"We support the Saudi Arabian military intervention in Yemen following President Hadi's request for support by 'all means and measures to protect Yemen and deter Houthi aggression.' As the UN Security Council has made clear, President Hadi is Yemen's legitimate president," said the FCO statement.

"The recent Houthi actions and expansion in Aden and Taiz is a further signal of their disregard for the political process. Any action taken should be in accordance with international law.

"Ultimately, the solution to the crisis must be a political one. The international community will continue to use diplomatic and humanitarian support to achieve long-term stability, avoid civil war, economic collapse and a deeper humanitarian crisis in Yemen."

The Houthis pushed south from Sana'a earlier this week, taking the Al-Alam military base outside Aden and threatening the city's airport before Saudi Arabia entered the conflict Thursday.

The US is providing military support to the Saudi-led coalition, and Jordanian jets have already carried out attacks on the country. Iran has condemned the military action.