Beijing: The United States has no role in pro-democracy protests in Hong Kong, President Barack Obama said in Beijing on Wednesday, despite Chinese accusations that foreign forces are involved.

"I was unequivocal in saying that the US had no involvement in fostering the protests that took place in Hong Kong," Obama told reporters at a joint press conference.

"These are issues ultimately for the people of Hong Kong and China to decide," he said.

"But I did make clear that US will encourage people`s right to express themselves and that elections in Hong Kong are reflective of the will of the people there."

Protesters have been occupying key intersections around the former British colony for more than six weeks calling for fully free leadership elections in 2017, but Beijing has insisted that all candidates be screened by a loyalist committee.

Xi responded that the Occupy Central movement is illegal and said Beijing "firmly supports" the Hong Kong authorities in their efforts to control the situation.

"Law and order must be maintained in any case, not only in Hong Kong but everywhere in the world," he said.

"Hong Kong`s affairs are exclusively China`s internal affairs," he added, and no other countries should interfere.