A United Nations mission tasked with overseeing a truce in war-torn Yemen came under fire but was unharmed in the flashpoint city of Hodeida Thursday, the UN said.

The head of the mission, Patrick Cammaert, and his team were ‘safe in Hodeida following reported shooting incident’, tweeted the spokesperson of the UN secretary general.

Speaking to AFP on condition of anonymity, a UN official confirmed that ‘shots were fired’ at Cammaert's convoy and that the retired Dutch general was ‘safe’.

The shooting comes one day after the UN Security Council unanimously approved an extended mission of up to 75 unarmed monitors to shore up a fragile ceasefire between the Iran-aligned Houthi rebels and government forces backed by Saudi Arabia and the UAE.

The ceasefire and observer mission was agreed on during talks last month in Sweden between the internationally recognised authorities and rebels.

The new monitors will be sent to Hodeida city and port as well as to the ports of Saleef and Ras Issa for an initial period of six months.

The port of Hodeida is the entry point for the bulk of Yemen's supplies of imported goods and humanitarian aid, providing a lifeline to millions on the brink of starvation.

The Houthis control most of Hodeida, while government forces are deployed on its southern and eastern outskirts.

The UN says the ceasefire, which went into force on December 18 in Hodeida, has been generally holding despite some clashes.

There have been delays in the redeployment of rebel and government forces from the city.