LABOR is pushing for another Senate inquiry into the European au pairs affair engulfing Peter Dutton, as the home affairs minister stokes a public feud with his former border force boss.

Ex-Australian Border Force commissioner Roman Quaedvlieg submitted a letter to a Senate committee after Wednesday’s initial inquiry, alleging Mr Dutton’s chief of staff Craig Maclachlan called him asking for help in June 2015.

Mr Dutton has labelled the letter as “entirely false and indeed fabricated”.

Labor Senator Murray Watt believes another public hearing is needed to get to the bottom of the saga.

“These latest revelations and contradictory evidence mean we do need to have another hearing,” he said.

“It’s very typical of Peter Dutton, when he’s under pressure, to start throwing mud at other people.”

Senior government minister Mathias Cormann said the ex-ABF chief’s allegations contained major factual inaccuracies.

“Mr Quaedvlieg is obviously not a credible witness here,” Senator Cormann said.

In the letter, Mr Quaedvlieg said Mr Maclachlan told him “the boss’ mate in Brisbane” had a problem with a prospective au pair who had been detained at the airport.

But Mr Dutton said Mr Maclachlan didn’t work for him until October 2015.

Mr Quaedvlieg rejected the claim he fabricated evidence, indicating he would reconcile the “anomaly” in dates and didn’t intend to debate facts through the media.

Senator Watt says there are 14 incidents involving tourist visas where the home affairs minister intervened. He’s calling for both men to appear before the committee inquiry.

Mr Dutton overturned his department’s decision to deport the woman and she was given a visa to stay in the country, despite her original plans to work for a former Queensland police colleague of Mr Dutton’s.

In an explosive rebuttal of Mr Quaedvlieg’s evidence, Mr Dutton called his mental health into question and said he was bitter about losing his job for misconduct.

Mr Quaedvlieg was sacked from his role after he helped his girlfriend get a job at Sydney Airport.

“I urge Dutton to desist from personal attacks and casting aspersions over my actions, motivation, integrity, reputation and mental health,” Mr Quaedvlieg said.

Mr Dutton is facing questions over whether he misled parliament by saying there was no personal connection between him and his former police colleague.

Mr Dutton has said he had not spoken to his former police colleague for 20 years but the man did call his office seeking help with the au pair’s case.