Britain adopted a tough line with China over the introduction of a new security law in its former colony of Hong Kong.

On Wednesday, Boris Johnson told the Commons that China was guilty of a “clear and serious breach” of its treaty with the UK — and as a result, nearly 3 million people in Hong Kong who have the status of “British National Overseas” would be given the right to come and live in Britain, initially for five years, and then offered the chance to settle permanently in the country.

The home secretary, Priti Patel, who will have to deal with the formidable logistics, backed up the Prime Minister: “Sad day for Hong Kong. China’s decision to enact this legislation constitutes a clear & serious breach of the Joint Declaration. UK will not look the other way. We will uphold our historic responsibilities & we will proceed to honour our commitment to those holding BNO (British national overseas) status.”

Boris told the Commons: “The enactment and imposition of this national security law constitutes a clear and serious breach of the Sino-British Joint Declaration. It violates Hong Kong’s high degree of autonomy.”