Delattre said the first priority following the escalation in fighting and the killing of former President Ali Abdullah Saleh "is to silence weapons and to allow complete and immediate humanitarian access in all Yemen and all its ports and airports".
Yemen's pro-Houthi Al Masirah television station said the coalition bombed Saleh's residence and other houses of his family members.
A video provided to AFP by the rebels showed what appeared to be a dead Saleh with a severe head injury, his body wrapped in a floral-print blanket.
Strongman Saleh had on Saturday bypassed his Houthi allies of three years, telling the Saudi-led military coalition in Yemen he was ready to negotiate if the crippling siege could be lifted.
Everyone knows that it was Iranian intelligence that provided Houthi militias with Saleh's plan of action, and gave clear instructions to take him and his companions out in cold blood.
The Houthis seized Sanaa in September 2014, forcing the government of president Abdrabu Mansur Hadi to relocate to the southern city of Aden.More news: Austrian court legalises same-sex marriage, declaring all other laws discriminatory
The government also reached out to Saleh's supporters with an offer of amnesty.
Faiqa al-Sayyid, a leader in Saleh's General People's Congress (GPC) party, said Saleh "was martyred in the defence of the republic".
Yemen's minister of information called upon the Houthi armed group to release the journalists and urged global organisations to "leave the status of passive onlookers and take acts to press the militias to stop tormenting all the Yemeni journalists", Muammar Al- Eryani told Saba Net.
"Today marked the failure of the conspiracy and treason, a black day for the forces of aggression", he said on Al- Masirah. They chanted slogans against Saudi Arabia and its allies.
Yemen's civil war has emerged as one of the main battlegrounds in the Saudi-Iranian rivalry for regional influence.
Saleh ruled Yemen for more than three decades until an Arab Spring uprising forced him to step down in 2012.More news: Starbucks is opening a store in China every 15 hours
Although the conflict began as a civil war between Shiite Houthis and the government of Saudi-backed former President Abdrabbuh Mansour Hadi, it has morphed into a proxy battle between Saudi Arabia and Iran, which has lent support to the Houthis.
The rebel alliance splintered last week, setting off heavy clashes between the Houthis and Saleh's forces.
"Aid workers can't travel and implement critical life- saving programmes".
Since November 29, armed clashes sparked by forces loyal to Saleh, have continued against Houthi forces that are at the forefront of a retaliatory war against the Saudi-led military coalition.
Coalition fighter jets carried out dozens of airstrikes, according to both sides of the conflict, bombing Houthi positions inside Sanaa and in other northern provinces.More news: Embattled Michigan Rep. John Conyers announces retirement