ADEN - The Red Cross warned Tuesday of a "catastrophic" situation in Yemen's main southern city Aden, as loyalist forces battled rebels in the streets backed by shelling by Saudi-led warships.

The Iran-backed Huthi rebels and their allies made a new push on a port in the central Mualla district of the city but were forced back by militia loyal to fugitive President Abedrabbo Mansour Hadi, witnesses said. Naval forces of the Saudi-led coalition, which has carried out nearly two weeks of air strikes in support of Hadi, shelled rebel positions across the city, they added. Spokeswoman for the International Committee of the Red Cross in Yemen, Marie Claire Feghali, said the humanitarian situation across the country was "very difficult... (with) naval, air and ground routes cut off."

She described the situation in Aden as "catastrophic to say the least". "The war in Aden is on every street, in every corner... Many are unable to escape," she said. Doctors Without Borders (MSF) said the situation was "worsening by the day".

MSF medics in Aden had "not received large numbers of casualties over the past few days... due to the difficulties faced in trying to reach a hospital," said Marie-Elisabeth Ingres, the organisation's Yemen representative. MSF has a team of 140 local staff and eight expatriates at a hospital in Aden. "Our priority is to find a way to send a supporting medical team," Ingres told AFP, adding a team was waiting in Djibouti "for a green light from the coalition".

The Red Cross hopes to deliver to Sanaa on Wednesday 16 tonnes of medical aid on a plane loaded in Jordan. Another plane carrying 32 tonnes of aid could follow on Thursday.

At least eight Huthis were killed Tuesday when coalition warplanes struck a position north of Aden, a military source said.  Other raids targeted air defence posts in the northeast of the central Taez province. Overnight fighting in Aden left at least 10 people dead. That was on top of at least 53 people killed over the previous 24 hours. Nationwide, more than 540 people have been killed and 1,700 wounded since March 19, the World Health Organization said Tuesday.  

The United States is speeding up arms supplies to a Saudi-led coalition battling Houthi fighters in Yemen, who are supported by Iran, Deputy Secretary of State Antony Blinken said on Tuesday.

Speaking to reporters on a visit to Riyadh, Blinken called for all political parties to commit to what he called a consensus political solution, and said Washington was stepping up intelligence sharing with the anti-Houthi alliance.

“Saudi Arabia is sending a strong message to the Houthis and their allies that they cannot overrun Yemen by force,” he said, referring to Riyadh’s leadership of a military campaign by several Arab states to prevent the Houthis from seizing Yemen.

“As part of that effort, we have expedited weapons deliveries, we have increased our intelligence sharing, and we have established a joint coordination planning cell in the Saudi operation centre.”

At the Pentagon in Washington, spokesman Colonel Steve Warren said the United States was looking to deliver munitions to its allies, including by accelerating pre-existing orders.

“It’s a combination of pre-existing orders made by our partner nations and some new requirements as they expend munitions,” Warren said, asked about Blinken’s remarks.

The United States has about a dozen personnel working in the joint coordination planning cell.

Warplanes from Saudi Arabia and Arab allies have been striking rebels fighting to oust US-allied Yemeni President Abd-Rabbu Mansour Hadi, in an attempt by the regional heavyweight to check Iranian influence in its backyard.

Gulf states aim to use military pressure to push the Houthis to resume a UN-backed political transition led by Hadi that was interrupted by the group’s seizure of the Yemen capital Sanaa in September.

Their takeover angered Riyadh, which sees the once obscure Zaydi group from the northern highlands as terrorists.

Observers have warned Al-Qaeda could exploit the fighting between Hadi's supporters and opponents to expand its control following the withdrawal of US troops overseeing a longstanding drone war against it. The evacuation of foreigners continued with three Indian planes carrying 604 passengers, including some Yemenis, from Sanaa to Djibouti, an airport official said.