The European Union will impose harsher sanctions on Syria, a senior EU official said Wednesday, as Russia tried to broker talks between the Syrian vice president and the opposition to calm violence. Activists reported at least 50 killed in military assaults targeting government opponents. Russian Foreign Minister Sergey Lavrov, who held emergency talks in Damascus with Syrian President Bashar Al-Assad Tuesday, is trying to end the 11-month-old bloody uprising, which has left more than 5,400 dead, according to the UN. Moscow launched the initiative Tuesday, just days after it infuriated the US by blocking a Western- and Arab-backed Security Council resolution supporting calls for Assad to hand over some powers to his vice president. Russian Prime Minister Vladimir Putin said outside forces should let Syrians settle their conflict “independently.” “We should not act like a bull in a china shop,” Putin was quoted by the Itar Tass news agency as saying. “We have to give people a chance to make decisions about their destiny independently, to help, to give advice, to put limits somewhere so that the opposing sides would not have a chance to use arms, but not to interfere. Lavrov told reporters in Moscow that Assad has “delegated the responsibility of holding such a dialogue to Vice President (Farouq) Al-Shara'a.” He blamed both Assad's regime and opposition forces for instigating the violence that has killed thousands of people since March. The regime's crackdown on dissent has left it almost completely isolated internationally and facing growing sanctions. The US closed its embassy in Damascus on Monday and five European countries and six Arab Gulf nations have pulled their ambassadors out of Damascus over the past two days. Germany, whose envoy left Syria this month, said he would not be replaced. Meanwhile, the Gulf Cooperation Council foreign ministers have rescheduled their meeting on Syria to Sunday in Cairo. “The meeting which was set to take place in Riyadh on Saturday will now be held in Cairo on Sunday ahead of the Arab League ministerial meeting” in the Egyptian capital, a GCC official said on the condition of anonymity. In Brussels, a senior EU official said the bloc will soon impose harsher sanctions against Syria as it seeks to weaken Assad's regime. The official said the new measures may include bans on the import of Syrian phosphates, on commercial flights between Syria and Europe, and on financial transactions with the country's central bank. The official said some measures would be adopted at the EU foreign ministers meeting on Feb. 27. But the Syrian crackdown continued. Troops bombed residential neighborhoods in the central city of Homs, the northern province of Idlib, southern region of Daraa and the mountain town of Zabadani, in what activists say is the regime's final push to retake areas controlled by the rebels. Activists said at least 50 people died in the shelling of Homs, which has been under a relentless regime offensive for the past five days. Hundreds are believed to have been killed there since Saturday.