Russian President Vladimir Putin, listens to King Abdullah II of Jordan during their meeting in the Kremlin, in Moscow, Russia, Tuesday, Aug. 25, 2015.

U.S. 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 of Iraq and Syria (ISIS) in Syria, an official source said.

Jordan reached an agreement with Moscow last October 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.

Diplomats say the Russian air force has stepped up in recent days bombing of mainly civilian targets in rebel-controlled towns in southern Syria, including parts of rebel-held Deraa city that are run by moderate rebel groups backed by Jordan.

Jordan has not publicly commented but the monarch, who has close personal ties with Putin, recently publicly expressed enthusiasm about the intensive Russian military campaign in Syria, saying it offered a window of opportunity and that Moscow had a key role in defeating the ultra-hardline militants.

Jordan, however, is Sunni-dominated and closely aligned with Washington, so Moscow’s deal with Jordan could mark a shift in the alliances engaged in the Syria conflict.

Putin has already forged close cooperation with the governments of Iraq, Syria and Iran, which are all part of a loose Shiite alliance pursuing different aims from those of the United States and its allies.

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