Chief Executive John Lee on Tuesday warned that any attempt to interfere with the legitimate operations of Hong Kong’s Economic and Trade Offices (ETOs) would only end up harming the economies of the countries that take such action.

He was speaking after a manager of the government’s ETO in London, Bill Yuen, was arrested with two others on suspicion of breaching Britain's national security law and charged with assisting Hong Kong intelligence officers.

"Any attempt to interfere with the work of the ETOs in different places will be against free trade and free economy, and will be harming the economy of the countries that try to do bad things to the operation of the ETOs," Lee said.

He told reporters that the duties of the trade offices are to liaise with foreign officials, businesses, think tanks and representatives of various sectors, to boost links and promote the economic and trade interests of the SAR.

"Any attempt to make unwarranted allegations against the SAR government is unacceptable," the chief executive said.

"The ETOs will of course pursue their duties full-heartedly and legitimately."

He also noted that the the Chinese Embassy in Britain has made serious representations to UK officials, while the SAR government is still waiting for British authorities to respond to its demand for more information on the allegations.

The Commissioner's Office of the Chinese Foreign Ministry in the SAR has accused Britain of arbitrarily arresting Chinese citizens and slandering the Hong Kong government, saying this violates the principles of international law.

Lee also said a photo of him and Yuen that is circulating online was taken more than two decades ago to mark their graduation from the Australian School of Policing.

The CE said that is the only impression he has of Yuen.