Electoral fraud is still taking place in Birmingham three years after a judge compared the city to a banana republic, an MP has warned.

John Hemming (Lib Dem Yardley) said he was aware of attempts to cheat the system in his own council ward, as the city prepares for local elections in May 1.

He raised his concerns in the House of Commons, after the judge who ruled in the Birmingham case in 2005 warned that nothing had improved.

In April 2005, Judge Richard Mawrey said electoral fraud in Birmingham would "disgrace a banana republic" as he dealt with six Labour councillors found guilty of vote-rigging.

Last week, he warned: "The opportunities for easy and effective electoral fraud remain substantially as they were on 4th April 2005."

Mr Hemming has called for changes in a House of Commons motion, backed by Conservative and Liberal Democrat MPs. The motion demands "urgent action from the Government to restrain fraud in the creation of electoral registers".

The MP, who is also a member of the city council representing South Yardley, said he was aware of "ghost voters" in his ward. These are names fraudulently added to the electoral register in order to obtain postal voting forms.

Ministers introduced reforms to combat fraud in the Electoral Registration Act 2006, which required people voting by post to sign a form and write their date of birth when returning their ballot paper.

But in his judgement last week, Mr Mawrey attacked the move as inadequate, saying council staff were not trained to match signatures and computers were unreliable.

Bogus ballots could still be slipped through and some genuine votes were rejected, he said.

The judge warned that vote-rigging was "childishly simple to commit and very difficult to detect".

Birmingham was hit by more election controversy recently when Labour was accused of winning the Aston ward in last year's Birmingham City Council elections by publishing lies about the Liberal Democrat candidate.

A judge is considering claims Labour councillor Muhammed Afzal published false claims about Saeed Aehmed, the losing Liberal Democrat candidate, alleging he was guilty of fraudulently obtaining disability improvement grants totalling £16,000, and had been arrested for postal vote fraud. A verdict is expected next week.