BRUSSELS (AFP) - EU foreign policy chief Josep Borrell on Wednesday (July 1) said it was essential that existing rights remain observed in Hong Kong after police made the first arrests under China's new national security law.

"The European Union considers it essential that the existing rights and freedoms of Hong Kong residents are fully protected," Borrell said in a statement.

These include "freedom of speech, of the press and of publication, as well as freedom of association, of assembly, of procession and of demonstration", the statement added.

Hong Kong police said they had arrested at least 180 people on Wednesday - including seven under a new national security law - as thousands of protesters defied a ban to rally on the anniversary of the city's handover to China.

Borrell said Brussels was "assessing the implications of such a law and will continue to raise its concerns in its dialogue with China".

EU foreign ministers in May had rejected the idea of imposing sanctions because of the law, saying they would not solve the crisis.

The Hong Kong question is now likely to be on the agenda again at the next EU foreign ministers meeting on July 13.