US ally Jordan's King Abdullah will hold talks in Moscow on Tuesday with Russian President Vladimir Putin on how to tackle "terror groups" led by Islamic State in Syria, an official source said. Jordan last October reached an agreement with Moscow to ensure Russian bombing of targets in southern Syria, which borders the country, does not target Western backed rebels known as the Southern Front - a grouping it supports as a buffer against the spread of hardline Islamist groups in an area that also borders with Israel.