The USinfo-icon-led coalition has only acknowledged killing of some 200 civilians in its alleged warinfo-icon against ISIS terrorist group in Syriainfo-icon and Iraqinfo-icon, rejecting the majority of civilian casualty reports as "non-credible."

"To date, based on information available, CJTF-OIR has assessed that, it is more likely than not, at least 188 civilians have been unintentionally killed by coalition strikes since the start of Operation Inherent Resolve," the US Combined Joint Task Force - Operation Inherent Resolve said on Monday in its monthly assessment of civilian casualties from the US-led coalition airstrikes.The figures are far below those estimated by outside groups during 2014-2016 period.

Air Wars, which monitors civilian deaths from international air strikes in the region, has estimated that at least 2,100 civilians have been killed in Iraq and Syria during the same period.

"CJTF-OIR regrets the unintentional loss of civilian lives resulting from coalition efforts to defeat ISIL in Iraq and Syria and express our deepest sympathies to the families and others affected by these strikes," the statement continued.

Human right groups also believe that the US is understating the civilian death toll, with Amnesty Internationalinfo-icon insisting that at least 300 people were killed in just 11 airstrikes that were probed.Overall, the US and its coalition partners conducted 17,005 strikes against purported Daesh targets as of December 30, with a total of 10,738 in Iraq and 6,267 in Syria, US military data shows.

According to the US Defense Department, mid-September airstrikes killed dozens of Syrian soldiers in the country's eastern province of Dayr al-Zawr, with officials saying later that the attacks were based on wrong intelligence.

On December 9, at least 90 Iraqi soldiers were killed when US Air Force fighter jets struck their position in Mosulinfo-icon.

The US military data shows that operation against ISIS in Iraq and Syria has cost $10 billion since 2014.