Yemen's government and the Houthi rebels have agreed on the first stage of a mutual pullout of forces from the port city of Hodeida, a key entry point for humanitarian aid, according to the United Nations (UN).

The agreement came after two days of meetings in Hodeida, a UN statement said.

The warring parties agreed to a ceasefire in the city and a prisoner exchange back in December after talks in Sweden but its implementation was stalled.

According to Yemeni government sources, the original ceasefire agreement was broken "within minutes".

The UN statement said both sides "made important progress on planning for the redeployment of forces as envisaged in the Hodeida agreement".

Yemen's government has been battling the rebels since 2014 in a conflict that has killed tens of thousands of people and raised fears of famine. 

A Saudi-led coalition entered the war on the side of the government in March 2015.

Peter Salisbury, a senior analyst at the Brussels-based International Crisis Group, said: "It's encouraging news that this has happened, as people had been losing faith in the process, causing fears that we'd soon see a return to combat in and around Hodeida."

He said the parties now need to implement the agreement, warning that "there is plenty of room for them to play games here, so we shouldn't get overexcited".

Foreign Secretary Jeremy Hunt hailed their progress, tweeting that the agreement must be "swiftly finalised & implemented" and urging progress on the prisoner release.

In November last year, Mr Hunt criticised both the Saudi-led coalition and Iran-backed Houthi rebels as he called for an end to the conflict.

At the time, the comments were seen as some of the government's strongest criticism of long-term ally and defence partner, Saudi Arabia.

AFP.