Winston Churchill considered blocking all immigration to Britain because he feared a growing "coloured population" was posing a threat to Britain's social stability.

Churchill, then 79, told Cabinet colleagues that he did not "want a parti-coloured UK". At a Cabinet meeting on February 3, 1954, the prime minister told colleagues: "Problems will arise if many coloured people settle here. Are we to saddle ourselves with colour problems in the UK?"

Churchill said immigrants were attracted to Britain by the welfare state and he said: "Public opinion in UK won't tolerate it once it gets beyond certain limits."

The notebooks reveal that the Cabinet considered ending the time-honoured tradition of allowing British subjects from overseas automatic residence in the country. A total ban on non-white immigrants, a quota system and the deportation of anti-social elements from overseas were among options considered.

David Maxwell Fyfe, later Viscount Kilmuir, the then home secretary, told colleagues there was evidence that more than a third of people convicted of living on immoral earnings were "coloured".

He said the "coloured population are resented in Liverpool, Paddington and other areas by those who come into contact with them". The home secretary said people who had no social contact with ethnic minorities were "apt to take a liberal view".

But Churchill, a committed imperialist, and his colleagues were aware that imposing too severe-a-system of controls could be problematic.

Maxwell Fyfe said: "We should be reversing the age-long tradition that British subjects have right of entry to mother-country of Empire. We should offend liberals and also sentimentalists."

The notebooks reveal that Churchill thought the way round the issue would be to let "public opinion develop a little more before taking action".

The Tory leader thought that would be "politically wise".

Until the Commonwealth Immigrants Act of 1962, all Commonwealth citizens could enter and stay in the United Kingdom without restriction.