Russia and Syria could face economic sanctions imposed by America and Britain as there is no appetite among Western powers for a military solution to protect civilians from their bombardment in the civil war.
British Foreign Secretary Boris Johnson, who spoke last week of the need to discuss "more kinetic options", said military solutions such as a no-fly zone or no-bombing zone over Aleppo are "extremely difficult".
Speaking after talks with US secretary of state John Kerry and other allies in London, Mr Johnson said Britain and its allies must work with the diplomatic "tools we have".
He insisted that Russia was "feeling the pressure" from the international community over its military support of the Bashar Assad regime.
Alongside fresh sanctions, Mr Johnson said other measures such as threatening those responsible for committing war crimes with justice at the International Criminal Court "will eventually come to bite".
Mr Johnson's comments indicate his call to consider a potentially more forceful solution to stop the Russian and regime bombing of civilians in Aleppo does not command the support of Western allies.
Speaking after the four-hour meeting at Lancaster House, the Foreign Secretary said: "No option is in principle off the table but be in no doubt that these so-called military options are extremely difficult and there is, to put it mildly, a lack of political appetite in most European capitals and certainly in the West for that kind of solution at present.
"So we've got to work with the tools we have - the tools we have are diplomatic.
"I think the most powerful weapon we have at the moment is our ability to make president Putin and the Russians feel the consequences of what they are doing."
Mr Johnson and Mr Kerry confirmed they were moving towards introducing fresh sanctions against "the Syrian regime and their supporters".
