China on Thursday warned of retaliatory measures if the the United Kingdom pushed ahead with plans to offer some three million Hongkongers a route to British citizenship amid a tit-for-tat spat over Beijing's new national security law in the special-status Chinese territory.

London and Beijing have locked horns over the national security law in Hong Kong, with both sides accusing the other of breaching the 1984 agreement underpinning the 1997 handover of the territory.EFE-EPA