Prime Minister David Cameron is to chair a meeting of the government's emergency response committee on Sunday to discuss an Islamic State (IS) video showing the beheading of British aid worker David Haines.
The campaign battle over Scottish independence took a bitter turn on Saturday when a senior nationalist warned businesses such as BP that they could face punishment for voicing concern over the impact of secession.
U.S. Secretary of State John Kerry said on Friday it was "not appropriate" for Iran to join talks on confronting Islamic State militants, as he appeared to play down how fast countries can commit to force or other steps in an emerging coalition.
Prime Minister David Cameron begged Scots on Wednesday not to rip apart Britain's "family of nations", visiting Scotland in an attempt to stem a steep rise in secessionist support ahead of a September 18 referendum on independence.
