Assad says he is fighting foreign- backed “armed terrorist groups” and his main allies – Russia, China and Iran – fiercely oppose any intervention intended to add him to the list of Arab autocrats unseated by popular revolts in the past year.China called US policy in the region “super-arrogant” and Russia’s Vladimir Putin warned against any action that bypassed the UN Security Council.Shells and rockets crashed into Sunni districts of Homs that have already endured weeks of bombardment.“Intense shelling started on Khalidiya, Ashira, Bayada, Baba Amro and the Old City at dawn,” opposition activist Mohammed al-Homsi said. “The army is firing from the main thoroughfares deep into alleyways and side streets.”The Syrian Observatory for Human Rights said nine people had been killed by the attacks on Baba Amro.Opposition accounts of grim conditions in Homs were echoed by those from other observers, including the Red Cross.Crowds gathered in the sensitive Damascus district of Kfar Souseh, home to several security agency headquarters, to mourn three young men killed in a protest on Sunday, a witness said.The International Committee of the Red Cross, which says the plight of civilians in Homs is worsening by the hour, has failed to secure a pause in the fighting to allow the wounded to be evacuated and desperately needed aid to be delivered.The relief agency has been pursuing talks with the Syrian authorities and opposition forces for days to secure access to besieged neighborhoods such as Baba Amro, where local activists say hundreds of wounded need treatment and thousands of civilians are short of water, food and medical supplies.Four Western journalists are trapped in Baba Amro, two of them wounded. An American reporter and a French photographer were killed there on February 22.French President Nicolas Sarkozy said he hoped the journalists could be rescued soon.“It’s very tense, but things are starting to move, it seems,” he said.Russia said its diplomats in Syria were trying to arrange a humanitarian truce in Homs, and suggested Western countries should pressure rebel forces there to cooperate.International consternation has grown over the turmoil in Syria, but there is little appetite in the West for military action akin to the UN-backed NATO campaign in Libya.Sarkozy, however, said Western powers hoped diplomacy could change minds: “We are putting pressure on the Russians first and the Chinese afterwards so that they lift their veto.”The new constitution drops a clause making Assad’s Ba’ath party the leader of state and society, allows political pluralism and limits a president to two seven-year terms.But this restriction is not retrospective, implying that Assad, 46 and already in power since 2000, could serve two further terms after his current one expires in 2014.The opposition dismisses the reforms on offer, saying that Assad, and his father who ruled for 30 years before him, have long paid only lip service to existing legal obligations.Juppé dismissed the referendum as a “sinister masquerade.”