The Syrian government dismissed calls for a ceasefire with rebels today, saying those fighting to topple Bashar Assad's regime have no unified leadership to agree to it.
UN envoy Lakhdar Brahimi had asked Iranian officials to help broker a truce during the Muslim holiday Eid, which falls later this month.
But the head of a UN-appointed panel probing alleged war crimes has warned that the presence of hundreds of radical Islamists threatens to aggravate the conflict.
Brazilian Professor Paulo Sergio Pinheiro said the panel is afraid foreign militants and radical jihadists were not fighting for democracy and freedom but have their own radical agendas.
Syrian rebels have claimed that they have agreed to set up a joint leadership, but it's more to convince international backers that they're a credible fighting force rather than to oversee a ceasefire.
As Aslef's annual assembly of delegates begins in Edinburgh tomorrow the general secretary explains the challenges his members - and workers across the country - face