NEW YORK, Oct. 14 -- The U.S. government is giving "false signals of assurance and support" to violent protesters in China's Hong Kong Special Administrative Region (HKSAR), said a renowned U.S. expert on China.

"With regard to the U.S. role, it has been deeply unhelpful," said Sourabh Gupta, a senior fellow at the Washington-based Institute for China-America Studies, in a written interview with Xinhua on Monday.

In terms of the U.S. official policy position, it is "a reasonable one: the Basic Law is supreme and all parties must adhere to it fully," said Gupta.

"The real problem has been the U.S. veiled intentions: to first stir the pot, and thereafter to fan the flames of protest by providing oxygen to the worst political and militant elements within the protest movement," he said.

"Not once have I heard the U.S. strongly condemn the unacceptable violence that we now casually see on a day-to-day basis ... even though both the Hong Kong government and the central government have scrupulously adhered to 'one country, two systems' (principle) throughout the protest period," he said.

The expert noted that the United States is "giving false signals of assurance and support to the worst elements within the protest movement ... and it is doing so knowingly."

"But it has no scruples running with the hares and hunting with the hounds, regardless of the consequences, so long as it can embarrass Beijing," he said. "This is what U.S. policy has come down to."

Gupta said the violent protests in Hong Kong "should have ended weeks ago," as the basic demands that they set to attain were achieved in early September in the form of the withdrawal of the extradition bill.

The HKSAR government announced on Sept. 4 that it would formally withdraw the proposed amendments to the Fugitive Offenders Ordinance and the Mutual Legal Assistance in Criminal Matters Ordinance.

At that point, the protesters "should have been toning down" their activity and "pressing their other immediate demands within a civil society dialogue framework," said Gupta. "Instead, they've gone in the opposite direction and are hoping to use their mobilization to effect changes within Hong Kong's system of representation within the LegCo (Legislative Council). This is just plain wrong."

"A deep and illuminating education of what 'one country, two systems' (principle) entails" is deeply needed, the expert noted.

As for the violent, radical fringe groups, Gupta said, they deserve "nothing less than heavy jail sentences."