The British Home Office confirms it will demand a £3,000 ($4,350) refundable bond for visas for "high-risk" visitors from six former colonies in Africa and Asia.
A statement on Monday says Britain will go ahead with the pilot scheme which has caused outrage, charges of discrimination and warnings of retaliation and that the move will hurt trade.
The statement sent by email did not say when the pilot would start. It said if the scheme is successful Britain would like to apply the bond "on an intelligence-led basis on any visa route and any country."
The countries affected are Nigeria, Ghana, India, Pakistan, Bangladesh and Sri Lanka.
Britain's Home Office said it hopes the bond system deters overstaying of visas and recovers costs of foreign nationals using public services.