The nuclear agreement between Western powers and Iran was broadly welcomed by politicians, former world leaders and Middle East experts.
Sri Lanka is putting on a show ahead of Friday's Commonwealth summit - but it is being overshadowed by accusations of human rights abuses.
William Hague and his Friends of Syria counterparts have agreed to "provide urgently all the necessary material and equipment" to rebels.
Foreign Secretary William Hague has called on the Syrian regime to hand over its chemical weapons within a "specific time frame" and said the "world must hold them to account" if they fail to do so.
At a joint press conference with US Secretary of State John Kerry and French Foreign Minister Laurent Fabius, Hague said: "(The regime needs to) give up its chemical weapons in a specific time frame and to credibly, reliably and promptly place them under international control for destruction.
"It is the Assad regime that has stockpiled these weapons and used them repeatedly against the Syrian people, so the pressure is on them to comply with this agreement in full.
"The world must be prepared to hold them to account if they don't."
Foreign Secretary William Hague has tweeted that he is in the French capital for talks with President Francois Hollande, the country's foreign minister Laurent Fabius and US Secretary of State John Kerry over Syria.
In Paris for talks with President Hollande, Secretary Kerry and FM Fabius on US-Russia agreement and ensuring Syrian compliance
Foreign Secretary William Hague said the international community has to make sure Syria's agreement to hand over its weapons "is not just a distraction tactic."
Mr Hague told a news conference in South Africa, "If there is a serious and genuine offer from the Assad regime to put its chemical weapons beyond use under international supervision, then that would be welcome and we would encourage that".
William Hague reiterated that Britain would push for "unfettered" UN access to Syria to deal with the humanitarian crisis in the country.
Foreign Secretary William Hague, speaking at a joint press conference with US Secretary of State John Kerry, said the two countries' "objectives and efforts remain closely aligned" despite the Parliamentary vote against UK military action in Syria.
US Secretary of State John Kerry has arrived at the Foreign Office in London for a meeting with British Foreign Secretary William Hague.
The meeting is expected to last around half an hour before the pair give a press conference.
US Secretary of State John Kerry will meet with Foreign Secretary William Hague this morning to discuss a possible US military intervention in Syria.
Foreign Secretary William Hague has called for a "strong international response" to the use of chemical weapons in Syria.
Speaking on the BBC's Andrew Marr show, he said: "Allowing the spread and use of chemical weapons in the 21st century, is an evil that we have to stand up to, one way or another.
"If it is decided that no-one will stand up to chemical weapons, that will be an alarming moment in the affairs of the world."
He said Labour had behaved in an opportunistic way by voting against intervention, but added that the government would not be seeking another vote on the matter:
"Our parliament has spoken. It is therefore up to other parliaments and they are about to speak."
Foreign Secretary William Hague is among EU foreign ministers meeting in Lithuania today, where they will be joined by US Secretary of State John Kerry, as the US seeks to secure support for possible strikes on Syrian targets.
Mr Kerry is also expected to hold talks with Mr Hague in London on Monday as part of his European tour.
Just spoken to Japanese Foreign Minister. We agreed more must be done to address Syrian humanitarian crisis
UK and Japan are two of the biggest bilateral donors to Syrian refugees. Hope we can do more together to save lives and alleviate suffering