AKIPRESS.COM - Russian defence officials say their aircraft carried out about 20 missions against the so-called Islamic State group (IS) on Wednesday.

The U.S. and Russian military will hold talks "as soon as possible" to avoid clashing in Syria, the countries' top diplomats say.

But the U.S. expressed fears the targets were non-IS opponents of Russia's ally, Syrian leader Bashar al-Assad. The U.S. is targeting IS with air strikes in both Syria and Iraq.

NATO said there had been little co-ordination by Russia with U.S.-led forces against IS, also known as ISIL.

The U.S. says it was informed of Wednesday's air strikes only an hour before they took place.

Russia's Foreign Minister Sergei Lavrov said there was a need to "establish channels of communication to avoid any unintended incidents". His U.S. counterpart John Kerry said talks will be held "as soon as possible," possibly as early as Thursday.

Mr Kerry added: "It's one thing to be targeting ISIL, but the concern, obviously, is that this is not what was happening."

France's Defence Minister, Jean-Yves Le Drian, told French MPs: "Curiously, they didn't hit Islamic State. I will let you draw a certain number of conclusions yourselves."

Syria's civil war has raged for four years, with an array of armed groups fighting to overthrow the government.

The U.S. and its allies have insisted that President Assad should leave office, while Russia has backed him remaining in power, reports BBC.