Yemen's Houthi rebels renew offensive to seize government's last northern stronghold of Marib
New clashes between pro-government forces - backed by a Saudi-led military coalition - and the rebels erupted after weeks of relative calm in the oil-rich and strategic region.
A government source told AFP that the Houthis had brought in reinforcements during that time.
"Fighting took place about 10 kilometres (six miles) west of Marib," the source told AFP on condition of anonymity.
"At least 20 government fighters were killed and 28 others injured," he said, adding that many rebels also died but no accurate count was available.
The Houthis have since 2014 held the capital Sanaa, which lies just 120 kilometres (75 miles) away and are mounting a fierce campaign to take Marib.
In the past 24 hours, government forces repelled "five attacks", the source said, a day after three pro-government fighters were killed and four injured in a missile attack on their camp in Marib.
The US State Department said on Friday it had formally notified Congress of its intention to revoke a terrorist designation against the rebels, which had been announced at the end of former president Donald Trump's administration.
The delisting move came a day after Trump's successor Joe Biden announced an end to US support for Saudi-led offensive operations in Yemen.
Humanitarian groups were deeply opposed to the terrorist designation, saying it jeopardised their operations in a country where the majority of people rely on aid, and that they have no choice but to deal with the Houthis, who control much of the north.
Saudi Arabia has been leading a military coalition since 2015 to support the internationally recognised government in a war that the United Nations says has resulted in the world's worst humanitarian crisis.
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