He said that although the practice was legal, French people no longer accepted it and that he had made a "mistake".

Mr Fillon`s campaign has been dogged by claims, which he denies, that his wife and two of his children were paid for non-existent parliamentary work.

Some in his party, The Republicans, feel he should step aside.

Recent polls have suggested that he may be eliminated in the first round of the presidential election in April, paving the pay for a possible run-off between centrist Emmanuel Macron and far-right leader Marine Le Pen.

Tarnished image

Mr Fillon, a 62-year-old former prime minister, has denied wrongdoing and strongly defended his wife, Penelope.

Media reports have said she earned €831,400 (£710,000; $900,000) as her husband`s parliamentary assistant between 1998 and 2012, and questioned how much work she had done.

It subsequently emerged that Mr Fillon had hired two of his children to act as lawyers, paying them €84,000 between 2005 and 2007 - when they were students.

Investigators have begun an inquiry into the reports. Mr Fillon said he would step down if placed under formal investigation.

Until the reports emerged, Mr Fillon was the front-runner for the presidential election, thanks in part to his image as a forthright, honest politician.

The practising Catholic enjoyed a landslide victory over Alain Juppe, another former prime minister, in a party primary in November.

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