Sudanese President Omar al-Bashir has threatened to kick out foreign election monitors, after they suggested next month's vote should be delayed.

Mr Bashir said if the observers intervened in Sudan's affairs, "we will cut off their fingers and crush them under our shoes".

The US-funded Carter Center recently suggested the 11 April election should be postponed amid security concerns.

The poll will be the first genuinely multi-party vote since 1986.

But opposition politicians have repeatedly suggested that the election should be put back amid chronic instability in the south and a continuing refugee crisis in the Darfur region.

Recovery from war

The Carter Center, which runs the only long-term monitoring mission in the country, said last week that the poll was "at risk on multiple fronts".

"Logistical preparations are straining the limited capacity of the NEC [National Election Commission]," the centre said.

"With a series of delays and changes in polling procedures, a minor delay in polling for operational purposes may be required."

Human Rights Watch said on Sunday that government repression of its opponents was and its tight control of the media was threatening the chances of holding a credible election.

However, the NEC said on Monday that the election would go ahead as planned.

And Mr Bashir told his supporters in the eastern town of Port Sudan: "We have accepted the arrival of foreign observers for the elections, but if they ask that the vote be postponed, we will expel them.

"We expect observers to say whether the elections are free and fair, but if they intervene in our affairs, then we will cut off their fingers and crush them under our shoes."

The general election will be the first since the end of a two decade civil war in 2005.

The 22-year conflict between the mainly Muslim north and the Christian and animist south claimed the lives of some 1.5 million people.

Violence between rival ethnic group continues to claim hundreds of lives each year in the south, making it difficult to ensure security during the election.

In Darfur, hundreds of thousands of people still live in refugee camps after a separate conflict.

Mr Bashir, who is wanted by international prosecutors for war crimes in Darfur, seized power in a bloodless coup in 1989.

He has been elected as president twice in polls which were boycotted by most opposition parties.

He remains popular in the north of the country and is expected to be re-elected as president.