This is apparently a move by UK to protect itself against changing tactics by violent Islamic extremists.
According to Associated Press British security and intelligence officials have warned of an increasing risk from Islamic extremists using South Africa as a transit point and planning plots there. They have said future attacks on Britain could be directed from countries other than Pakistan — where dozens of Britons with family ties have traveled for terrorist training or have been linked to recent terror plots.
Officials have said terrorists and criminals are exploiting the availability of stolen or forged South African passports to gain access to Britain and other countries.
Siobhan McCarthy, a spokeswoman for South Africa's Home Affairs ministry, said steps have been taken to prevent corrupt officials issuing bogus passports, and to make the documents harder to copy.
Prosecutors in the London trial of several men accused of plotting to blow up at least seven trans-Atlantic commercial flights said last year that a suspect had flown into Britain from South Africa to lead the final stages of the plan.
Mohammed Gulzar traveled to Britain from South Africa via Mauritius in July 2006. Gulzar was acquitted on all charges over the plot, but law enforcement officials said the case highlighted the potential for terror suspects to use South Africa as a transit point.