SANAA, Yemen (AP) — Heavy fighting between the Saudi-led coalition battling Yemen's Shiite rebels along the country's west coast has killed more than 165 people from both sides, Yemeni officials said on Saturday, amid efforts by the U.N. special envoy to restart peace talks between the warring parties.

The security officials said the battles have been concentrated over the past two days in al-Tuhytat district, south of the key port city of Hodeida. It comes as Yemenis continue to flee the west coast seeking shelter in safer areas. They spoke on condition of anonymity because they were not authorized to brief the media.

Yemeni government forces, backed by air cover from the Saudi-led coalition, are seeking to expand their control along the west coast and especially in Hodeida, a vital lifeline for Yemen's import-dependent population. The coalition had in June launched an offensive to retake the city from the rebels, known as Houthis, but paused it last week in support of the U.N. peace efforts.

The government of self-exiled Yemeni President Abed Rabbo Mansour Hadi called for rebels' "unconditional withdrawal" from the city. The Houthis have long refused handing over Hodeida but recently offered to submit the port to U.N. control as part of a cease-fire in the city.

U.N. Special Envoy Martin Griffiths has held talks with both sides in recent weeks in the hopes of preventing a full-scale coalition assault on Hodeida. He expressed optimism after his latest meeting with top Houthi leaders. The officials added that Griffiths is expected to hold another meeting with Hadi on Monday.

Impoverished Yemen has been embroiled in a civil war since March 2015 as the Saudi-led coalition aims to restore Hadi's government to power.