Afghan President Hamid Karzai on Wednesday condemned allegations of child abuse by two British soldiers in Afghanistan, calling it an "immoral" action by the troops.

The London-based Sun newspaper reported that two British soldiers had been arrested after they allegedly encouraged an Afghan boy and a girl, both aged 10, to touch the soldiers through their clothes.

The accused pair also reportedly filmed the children in the act and then showed the recordings to other soldiers.

"The government of Afghanistan has been deeply disturbed by the reports," Karzai said in a statement on Wednesday. "The government strongly denounces the 'immoral' act by the British soldiers, calling it a child abuse."

The allegation of child abuse by the two international troops comes a week after a video released online, showing three US Marines urinating, apparently on dead Taliban fighters.

"The government of Afghanistan is immensely disgusted by the risen recent incidents of immoral nature among foreign soldiers that clearly undermine public confidence and the Afghan people’s cooperation with foreign troops."

The NATO-led International Security Assistance Force (ISAF) said that a United Kingdom royal military police investigation is currently underway to look into allegations of inappropriate behavior by the two soldiers.

"Allegations of this nature are taken very seriously, and the investigation will determine the validity of the behavior in question," it said.

In another scandal involving US troops in Afghanistan, soldiers who named themselves the "Kill Team" targeted civilians and killed at least three in the volatile southern province of Kandahar in 2010.The US military has begun prosecutions against five soldiers in the case. (DPA)