A Saudi-led coalition struck northern provinces of Yemen on Saturday in a third consecutive night of heavy air strikes, the Houthi rebels said, following their shelling this week of Saudi border areas.

More than 100 air strikes hit areas of Saada and Hajjah provinces, including the districts of Haradh, Maidi and Bakil al-Mir, the Houthis said.

It was not possible to independently verify the number or location of strikes but coalition jets destroyed a Houthi headquarters in Al Talah and tanks and military vehicles in al-Baqah in Saada province, Saudi state television reported.

Other strikes targeted Sanaa airport's runway, an official there said, and Houthi targets in the Al Sadda district of Ibb in central Yemen, residents there said.

In the southern port city of Aden, clashes continued on Friday and Saturday in the central Crater, Khor Maksar and Mualla districts as the Houthis and forces loyal to Saleh shelled local militias trying to oust them from the city.

However, the Houthis were pushed back from parts of Dar al-Saad in the city's north into Lahj Province, local militias send, and faced fighting in al-Dhala Province.

The coalition has bombarded the Houthis and army units loyal to former president Ali Abdullah Saleh since March 26, but eased back on the strikes in late April and on Friday offered a five-day truce starting on May 12 if other parties agreed.

The Saudis and nine other Arab countries, backed by the US, Britain and France, hoped to force the Houthis back to their northern heartland and restore the exiled government of President Abd-Rabbu Mansour Hadi, who is in Riyadh.

The Houthis are mainly drawn from the Zaydi sect of Shi'ite Islam that predominates in Yemen's northern highlands. They took advantage of political chaos to seize Sanaa and then advance further south over the past year, aided by Saleh.

Riyadh fears the Houthis will act as a proxy for their main regional rival, Shi'ite Iran, to undermine Saudi security, and that their advance into Sunni regions will add a sectarian edge to the civil war, strengthening an al Qaeda group in Yemen.-Reuters