Four Egyptian naval vessels have sailed on Thursday through the Suez Canal en route to Yemen to support a Saudi-led operation against anti-government rebels, a military source said.

The source told Al-Ahram Arabic news website that warships from a Red Sea base had moved to the Gulf of Aden to secure the regional waters.

"A state of highest alert has been declared and our forces are on standby and ready to quickly move once a decision to intervene in Yemen is announced," the source said.

Saudi Arabia said more than ten countries, including four Gulf monarchies, had joined the coalition to prevent the fall of Yemeni President Abd-Rabbu Mansour Hadi, and stop the advance of Shia Houthis rebels who have seized the capital.

Egypt has announced its political and military support for the Saudi-led campaign in Yemen and said it would provide ground troops if necessary.

Egyptian Foreign Minister Sameh Shoukry reiterated, during an Arab League meeting on Thursday, calls for a joint Arab military force to keep at bay the growing threat of militants in the region.