By Mohammed Mukhashaf and Mohammed Ghobari
ADEN/CAIRO (Reuters) - Yemen's Houthi militia battled its way into Aden's Tawahi district on Wednesday despite Saudi-led air strikes, strengthening its hold on the city whose fate is seen as crucial to determining the country's civil war.
The fighting across Yemen killed 120 people on Wednesday, mostly civilians, including at least 40 who were trying to flee the southern port city of Aden by a boat that was struck by Houthi shells, rescue workers and witnesses said.
The Houthis and ex-army forces loyal to former president Ali Abdullah Saleh have besieged Aden for weeks in an effort to end resistance in the city where President Abd-Rabbu Mansour Hadi briefly based his government before fleeing to Saudi Arabia.
Hadi's Foreign Minister Reyad Yassin Abdulla appealed for the international community to intervene to stop the Houthi assault on Aden in a televised news conference from Riyadh.
Insisting that the city had not fallen, he described the militia as "the killers of men and children" and said Aden's residents had appealed to Saudi Arabia for help "in the name of the brotherhood of blood and religion".
Locals said the Houthis had penetrated the historic district of al-Tawahi, where the presidential palace, main port and Aden television station are located. Fighting still raged, they said.
Saudi Arabia regards the Houthis, who are mostly members of the Zaydi Shi'ite sect from Yemen's northern highlands, as a proxy for its main regional foe Iran and has led a Sunni Arab coalition in strikes aimed at restoring Hadi's government.
Coalition jets have bombarded the Houthis and Saleh's forces in and around Aden, have dropped supplies for local allies, and have deployed there Yemeni soldiers who were retrained in Gulf states, it has said.
Meanwhile, in Yemen's far north, coalition airstrikes killed 43 civilians, Houthi sources said, following the death of five Saudi civilians on Tuesday in mortar and rocket fire, the first such deaths in the kingdom since the campaign began on March 26.
More than 30 airstrikes hit Saada province and there was heavy artillery fire from across the border, local sources said.
The figure could not be independently verified.
HUMANITARIAN DISASTER
The conflict has disrupted imports to Yemen, where about 20 million people or 80 percent of the population are estimated to be going hungry, a statement by the United Nations and the Yemen International NGO Forum said.
A shortage of fuel has crippled hospitals and food supplies in recent weeks, and the U.N.'s World Food Programme (WFP) has said its fuel needs have leapt from 40,000 litres a month to 1 million litres.
The WFP also dismissed an announcement by the Saudi alliance of a possible truce in some areas to allow for humanitarian supplies, saying a permanent end to hostilities was needed.
U.S. Secretary of State John Kerry said on Wednesday that Washington was concerned about the dire humanitarian situation and pledged $68 million for relief work in the country.
He told journalists in Djibouti that he would discuss a possible pause in fighting with Saudi officials later on Wednesday to try to get food, fuel and medicine to civilians
"We have urged all sides to comply with humanitarian law to take every precaution to keep civilians out of the line of fire," he said.
Aden residents said at least 30 Houthi gunmen and 10 local fighters died in overnight fighting, including a local commander, Brigadier General Ali Nasser Hadi, who was reportedly killed by a Houthi sniper.
Another nine people were killed and 18 were injured in air strikes on a police academy in Dhamar province, south of the capital Sanaa, the Houthi-run Saba news agency said on Wednesday.
The United Nations said on Tuesday at least 646 civilians had been killed since coalition air strikes began, including 131 children, with over 1,364 civilians wounded.