LONDON (Reuters) - Prime Minister David Cameron said on Monday a Chinese decision to prevent a committee of British lawmakers from visiting Hong Kong was mistaken and heightened concerns about the situation in the former British colony.

On Sunday, the chairman of parliament's foreign affairs committee said Chinese embassy officials had told him he and other British lawmakers would be refused entry to Hong Kong to undertake research related to an inquiry about progress towards democracy there.

Cameron sharply criticised that decision on Monday, escalating a diplomatic dispute that threatens to damage relations between London and Beijing at a time when economic and trade ties between the two are becoming closer.

"His view is that the decision with regard to the foreign affairs committee is a mistaken one," Cameron's spokesman told reporters, saying Foreign Secretary Philip Hammond had raised a complaint about the matter with his Chinese counterpart last week on the sidelines of a meeting in Vienna.

"It's counter productive because it only serves to amplify concerns about the situation in Hong Kong, rather than diminishing concerns."

Chinese Foreign Ministry spokeswoman Hua Chunying had previously said Beijing had every right to decide who it let into the territory, calling the British committee's determination to visit an "overt confrontation."

The spat comes as thousands of pro-democracy activists in Hong Kong forced the temporary closure of government headquarters after clashing with police over the way the city's next leaders will be elected in 2017.