China's top legislative panel has said Beijing must intervene in a Hong Kong political dispute to deter advocates of independence for the city, calling such acts a threat to national security.

The official Xinhua News Agency reported late Saturday that the Standing Committee of the National People's Congress said Beijing could not afford to do nothing in the face of challenges in Hong Kong to China's authority.

The dispute centers on a provocative display of anti-China sentiment by two pro-independence lawmakers at their swearing-in ceremony last month.

Xinhua cited a statement from the legislative panel as saying the two lawmakers' actions "posed a grave threat to national sovereignty and security."

The panel is discussing interpreting an article in Hong Kong's constitution covering oaths taken by lawmakers.