Britain and America have sought to reassure Syria's opposition forces that stronger international help is imminent as US Secretary of State John Kerry vowed not to leave them "dangling in the wind".
Mr Kerry urged those resisting the Assad regime's crackdown not to boycott a meeting of international allies as he kicked off an 11-day tour of European and Middle East capitals in London. Foreign Secretary William Hague said he was poised to "significantly increase" assistance after securing a relaxation of an EU embargo on non-lethal equipment.
Declaring Washington's "special relationship" with the UK "stronger than ever", Mr Kerry said it was "no accident" he had chosen London as his first overseas visit just weeks after taking office.
But after a 10 Downing Street breakfast with Prime Minister David Cameron and talks with Mr Hague, he declined to take sides in Britain's dispute with Argentina over the Falkland Islands. Asked if the US would "respect" any vote by islanders to remain British, he said neither he nor US President Barack Obama would comment in advance.
The Prime Minister's official spokesman, asked if Number 10 was disappointed with Mr Kerry's response, noted that the US "has a very long-standing position" on the issue.
Top of the agenda for the talks were efforts to restart the Middle East peace process, the proposed EU/US free trade agreement and ongoing tensions over Iran's nuclear ambitions.
But a press conference with Mr Hague was dominated by questions about the next steps to end the bloodshed in Syria after the opposition said it would stay away from a meeting of the "Friends of Syria" group in Rome on Thursday because of what it called "the world's silence".
Mr Hague said he shared their intense frustration that "more than 70,000 people have been killed and there has been no sign of a political or diplomatic breakthrough". But he said he hoped to be able to set out escalated assistance within weeks.
"We believe we must significantly increase our support for the Syrian opposition on top of our large contributions to the humanitarian relief effort, and we are preparing to do just that," he said. "In the face of such murder and threat of instability our policy cannot stay static as the weeks go by."
Mr Kerry said he could not give details of what he hoped to be able to offer in Rome as it would be the subject of talks over coming days. He said: "But I want our friends to know that we are not coming to Rome simply to talk. We are determined that the Syrian opposition is not going to be dangling in the wind, wondering where the support is, if it is coming."