The UK said it was ready to â€˜significantly increaseâ€™ its support for Syriaâ€™s opposition
The Syrian opposition has agreed to attend an international summit in Rome, after the US and UK â€œpromised specific aidâ€ to the Syrian people.
The group had previously announced it would boycott the talks because of â€œthe worldâ€™s silenceâ€ over the violence.
US Secretary of State John Kerry and British Foreign Minister William Hague earlier confirmed there would be more support for Syriaâ€™s opposition.
Mr Kerry was in London as part of his first foreign trip since taking office.
The Syrian oppositionâ€™s announcement came amid reports of a deadly explosion and heavy fighting in an eastern part of the Syrian capital, Damascus.
It also emerged on Monday that a member of the UN peacekeeping force monitoring the ceasefire between Israeli and Syrian troops in the demilitarised Golan Heights was missing.
â€œWe can confirm that a staff member is not accounted for and we are in touch with the relevant parties to determine what has happened,â€ UN spokesman Eduardo del Buey told the Associated Press.
â€˜Alleviate the sufferingâ€™
After meeting Mr Hague and British Prime Minister David Cameron, Mr Kerry called Syrian Opposition Council President Moaz Al-Khatib and encouraged him to join the Rome talks on Thursday. No further details have been released about the conversation.
But on Monday evening, Mr al-Khatib said in a Facebook post that his group would fly to Italy.
â€œAfter discussions with coalition leaders and various calls, the coalition leadership has decided to stop the suspension of the visit to the Friends of Syria conference in Rome,â€ the statement said.
John Kerry, less than a month into his new job as the USâ€™ top diplomat, has already hit the ground running. At the Foreign and Commonwealth Office on Monday, he appeared to speak directly to the Syrian opposition from his podium in the room full of US and UK press – citing his new role as a â€œripeâ€ moment to move forward.
â€œWe understand the Syrian people want to see results and I would say to al-Khatib so do we,â€ he said. The state department said later that Mr Kerry called Mr Khatib directly. A spokesman told the broadcaster al-Arabiya they would send a delegation.
And then came the clear signal from Syrian Foreign Minister Walid al-Moallem that the Assad regime fears for its future: they are prepared to hold talks with the armed opposition. But the rebels are unlikely to sit down with them.
More specifically Mr Kerry and Mr Hague had both offered guarantees â€œto alleviate the suffering of our peopleâ€.
The talks would be â€œused as a practical way to reassess relations between the Syrian opposition and international partiesâ€, the post said.
Mr Kerry is due to meet Syrian opposition members and Russian Foreign Minister Sergei Lavrov in Berlin on Tuesday.
The US Secretary of State, who succeeded Hillary Clinton, is on an 11-day tour of Europe and the Middle East.
Speaking in London, Mr Kerry said he understood Syrians wanted results from the summit and promised it would not just be a talking shop.
â€œWe are determined that the Syrian opposition is not going to be dangling in the wind, wondering where the support is, if it is coming,â€™â€™ he told reporters after meeting Mr Cameron and Mr Hague.
â€œWe are not going to let the Syrian opposition not have its ability to have its voice properly heard in this process.â€
Mr Hague also said the UK was preparing to â€œsignificantly increaseâ€ its support for Syriaâ€™s opposition.
Earlier, the Syrian foreign minister Walid Muallem had announced his government was ready for talks with its opponents, even armed rebels.
John Kerry: â€œThe Syrian people deserve better than the horrific violence that invades and threatens their everyday livesâ€
Meanwhile, a massive blast was reported in the al-Qaboun neighbourhood in Damascus on Monday evening.
Several Syrian security were killed in the explosion caused by a car bomb, according to the Syrian Observatory for Human Rights, a UK-based activist group.
Rebels were clashing with security forces and mortars had been fired in the area, it added.
The SOHR is one of the most prominent organisations documenting and reporting incidents and casualties in the Syrian conflict.
The group says its reports are impartial, though its information cannot be independently verified.