The US-led coalition has confirmed that it killed 50 civilians during its airstrikes against what it called Daesh positions in Iraq and Syria in August.

The coalition released the figure in a Friday statement, saying the casualties were from 14 incidents.

The statement claimed that the total number of civilians it has killed in both countries has reached 735 since it began airstrikes there in 2014.

The reported estimate of civilian deaths comes as independent monitors have time and again challenged such reports and revealed that the US-led military campaign has significantly inflicted more civilian casualties.

Airwars, a UK-based non-profit monitoring group, says at least 5,486 civilians have been killed by coalition air strikes in Iraq and Syria over the past three years.

Smoke billows after a US-led airstrike on the Syrian city of Raqqah on July 15, 2017.

The co-called Syrian Observatory for Human Rights says a total of 42,234 documented airstrikes in the country have resulted in a minimum estimate of some 7,000 civilian deaths by the US-led coalition between 2014 and 2017.

The US-led coalition of 68 nations has been conducting airstrikes against what are said to be Daesh targets inside Syria since September 2014 without any authorization from the Damascus government or a UN mandate. Such air raids began in Iraq in August of the same year.

The military alliance has repeatedly been accused of targeting and killing civilians. It has also been largely incapable of fulfilling its declared aim of destroying the Daesh Takfiri terrorist group.