On Tuesday, the government stressed that lawmakers’ oath-taking was a “constitutional requirement” and the form of the oath was prescribed by the Oaths and Declarations Ordinance.

“If a member swears his or her oath in a manner or form that is inconsistent with the ordinance ... the oath offends the Basic Law and will therefore be unlawful and of no legal effect,” the statement read.

“Any person who declines or neglects to take an oath duly requested which he or she is required to take shall vacate office or be disqualified from entering it.”

He said he planned to get round the rules by ways that could satisfy the mini-constitution while not compromising his position.

But fellow localist Eddie Chu Hoi-dick said he would most probably take the oath in a proper way. “I don’t think it’s important to make a fuss over the oath,” he said.

Incoming lawmaker Starry Lee Wai-king, chairwoman of the government-friendly Democratic Alliance for the Betterment and Progress of Hong Kong, said she would raise the issue with the Legco secretariat if anyone failed to meet the oath-taking requirement.

Pro-Beijing newspaper Ta Kung Pao reported on Tuesday that Beijing could resort to an interpretation of the Basic Law if Hong Kong’s courts failed to make a ruling on lawsuits arising from lawmakers’ failure to take their oath properly.

“No one should underestimate the central government’s determination in getting rid of ‘Hong Kong independence’,” the report quoted an “authoritative source” as saying.

But a source familiar with the government’s position said the localists were expected to exercise restraint, otherwise they would not be able to assume office.

“Officials are more worried about localists calling for Hong Kong independence or self-determination at [future] Legco meetings,” the source said.

The Basic Law states that lawmakers are immune from legal action for statements made in Legco meetings.