US sanctions have no legal effect on the Chinese mainland and in Hong Kong, the China Banking and Insurance Regulatory Commission (CBIRC) addressed in its statement on Thursday, stressing that sovereignty is essentially non-negotiable and core interests are impossible to be compromised.

As part of an escalating anti-China campaign, the US has unilaterally imposed a series of sanctions since last August on more than a dozen of Chinese officials including Chief Executive of the Hong Kong Special Administrative Region (HKSAR) Carrie Lam. The sanctions included allowing US authorities to freeze these officials' assets and prohibit US firms from doing businesses with them.

The US has violated international law and basic norms governing international relations by unilaterally imposing sanctions on Chinese citizens and legal entities in accordance with its domestic laws, CBIRC noted in the statement.

"We will firmly uphold national sovereignty, security and development interests, support financial institutions in conducting their businesses in accordance with the law, and provide fair and quality financial services to all clients, including citizens from Hong Kong and the mainland," it said.

According to the CBIRC, a number of new foreign institutions have been established in the banking and insurance industries over the past year and quite a few of them are from the US. Both Chinese and US enterprises and citizens have benefited from the extensive financial cooperation between the two countries.

"A stable China-US relationship not only serves the fundamental interests of the people in the two countries, but also represents the common expectations of the international community," CBIRC noted.