According to the BBC's Inside Sport programme, which cited sources at Downing Street, the ban is one of several options being considered to try to ensure Zimbabwe's cricket team cannot tour England next year.

Brown's office declined to comment and a spokesman for the foreign office would not comment on a complete ban, but said that the government was concerned about future cricket tours by countries ruled by "dictators" such as Zimbabwean President Robert Mugabe.

"Although there are no sporting sanctions on Zimbabwe, international sports should never be a way for dictators to publicise their misrule," the spokesman said.

"If the situation does not improve in Zimbabwe, we would not want to see the Zimbabwe team tour here in 2009, nor the England cricket team tour there in 2012."

Zimbabwe reacted angrily to the reports, saying such a ban would be "racist".

"We are not surprised by that. It's their country, they have the freedom to decide who goes in and out," said Deputy Information Minister Bright Matonga.

"But it is a racist move because the majority of Zimbabwe cricket players are black and the game is now being managed by blacks. This is the same Britain that allowed its cricketers to tour apartheid South Africa.

"This is a racist ploy, if we had an all-white team, they would have allowed it to tour," he added. "Sport should be a unifying force, not a political battleground."

The government has long been sharply critical of Mugabe, accusing him of human rights abuses and of ruining a once healthy economy.

The 84-year-old Zimbabwean leader, who has ruled for 28 years, is running for another five-year term in the elections later this month.

He has vowed to defeat his rivals, including former finance minister Simba Makoni and MDC leader Morgan Tsvangirai.