The Syrian government has rejected a report which claims to show the systematic torture and killing of around 11,000 prisoners, calling it "politicised" and an attempt to undermine peace talks in Geneva.
William Hague called said that those responsible for the "horrific" images should be held to account.
The Foreign Secretary said:
"We have done a great deal... this (publication) has been done with the assistance of the Qatari government so not entirely a private initiative.
"I've seen a lot of this evidence, it is compelling and horrific and it is important those who have perpetrated these crimes are one day held to account.
"The United Kingdom has done a great deal in the documentation of human rights abuses. Part of the support we have given to moderate political forces in Syria is to train human rights activists in the recording and documentation of crimes, many of which have therefore come to the world's attention.
"We will do more of that."
A report claims evidence of "industrial scale killing" and torture of prisoners of the Syria regime. This article contains graphic images.
A report by leading international lawyers accuses Syria of systematic torture. A warning that this article contains graphic images.