Foreign Secretary William Hague has called on the United Nations to condemn violence in Syria which has left up to 140 protesters dead.
Syrian President Bashar al-Assad has launched a brutal crackdown on campaigners pleading for political reform in the Arab nation.
Security forces backed by tanks and snipers launched a ferocious assault on defiant cities and towns on Sunday, leaving scores dead.
But Mr Hague ruled out confronting the regime, saying there is no international appetite for military action.
Instead, he wants "additional sanctions" to ratchet up the pressure on Assad's regime.
"We want to see stronger international pressure all round," said Mr Hague. "To be effective that can't just be pressure from Western nations - that includes from Arab nations, it includes from Turkey, which has been very active in trying to persuade President Assad to reform instead of embarking on these appalling actions."
He added: "I would also like to see a United Nations Security Council resolution to condemn this violence, to call for the release of political prisoners and call for legitimate grievances to be responded to."
Speaking on the BBC Radio 4 Today programme, Mr Hague admitted that agreeing a resolution would be "quite difficult", saying: "There are nations on the Security Council opposed to any resolution - or they have certainly been in recent weeks. We will revisit this in the coming hours and days."
Mr Hague said UN-backed military action against Syria is "not a remote possibility", describing the situation as different from Libya when the UN passed a resolution endorsing armed intervention.
"It is a very frustrating situation. The levers we have are very limiting," he added.