Ankara-backed Syria rebels claim killing four Russian soldiers

A Syrian rebel force has said that they have killed four Russian soldiers in the war-torn country's north as the regime and its ally Moscow have stepped up their bombardment of the area.

The Turkish-backed National Liberation Front (FNL) said in a statement on Wednesday that its forces shelled a concentration of Russian troops at a base in the north of Hama province, killing four.

The NLF controls parts of the rebel stronghold of Idlib, which has come under increasing bombardment in recent weeks.

Russia's Ministry of Defence has yet to comment on the report.

The United States on Tuesday urged Russia to abide by its commitments and end an "escalation" in the Idlib region after a monitor said air strikes killed 10 civilians.

The escalation has killed more than 200 civilians since February, the United Nations said last week.

Idlib and parts of surrounding provinces have been protected from a massive regime offensive by a September deal inked by Damascus ally Russia and rebel backer Turkey.

But the region of some three million people has come under increasing bombardment since the jihadist Hayat Tahrir al-Sham (HTS) group took over most of it in January.

The jihadists reached a ceasefire agreement with the Turkey-backed rebels in January after clashes between the rival groups.