Britain has summoned Syria's ambassador in London to voice concerns about media reports a Syrian diplomat has been intimidating Syrian activists in Britain.

Britain's Foreign Office said Tuesday that Ambassador Sami Khiyami was called to a meeting with a British official on Middle East affairs, Christian Turner.

A statement said Turner noted the intimidation alleged in the reports would amount to a “clear breach of acceptable behavior.” He said if such claims prove to be true, the Foreign Office will respond “swiftly and appropriately.”

British newspapers have reported that Syrians involved in anti-government protests in Britain have been intimidated by a Syrian embassy diplomat in London. The reports also allege members of the protesters' families have been harassed by authorities in Syria.

Britain is one of several European countries that have condemned Syria for its violent crackdown on protesters. British Foreign Secretary William Hague has called for Syrian President Bashar al-Assad to implement reforms or step aside.