Britain announced on Thursday that it is considering expanding visa requirements to citizens from 11 additional countries including South Africa.
Nationals from more than 100 countries, equivalent to three-quarters of the world's population, need a visa to come to the United Kingdom.
But following a "Visa Waiver Test" of all non-European countries, the government said there is a "strong case" to add 11 more.
These are: Bolivia, Botswana, Brazil, Lesotho, Malaysia, Mauritius, Namibia, South Africa, Swaziland, Trinidad and Tobago, and Venezuela.
The test looked at the level of risk nationals from countries posed in terms of illegal immigration, and crime and security.
Britain said visitors from these countries will now need a six-month visa. That will become a permanent requirement unless the "risk" posed by national from these countries is significantly reduced by the end of the year.
Under a new system introduced in April, all visa applicants need to have their fingerprints checked before travelling.
Border and Immigration Minister Liam Byrne said two million fingerprints of foreign nationals had already been examined.
"Now we need to decide how to widen the visa net. We cannot and will not shy away from going wider and will wherever we think there's a risk to the UK," he said.
