France's high commissioner for pensions, Jean-Paul Delevoye, has stepped down from his post.

The 72-year old resigned on Monday after failing to disclose a high-paying private sector job while he was in office, according to the government.

^{CGTN Europe's Holly Hudson reports from Paris on the latest developments}

Delevoye had been under pressure since last week over his admission that he held 13 private sector posts, both paid and unpaid.

These included commitments with the education think tank Parallaxe, the French Federation of Insurers and the charitable arm of rail operator, SNCF. 

According to the AFP news agency, Delevoye had been paid at least $137,000 for the various administrative roles since being given the responsibility of overhauling the pension system. 

Delevoye had said he would reimburse the sum as several ministers came out in support of him on Sunday.

In a statement to AFP Delevoye said his credibility had been undermined by "violent attacks" by unions and opposition leaders seeking to discredit a pensions overhaul he said "is essential for France".

President Emmanuel Macron's office said that it had accepted Delevoye's resignation and a replacement would be appointed "as soon as possible."

"The president hails his personal commitment and his work on the pension reform," it said. "His withdrawal allows the clarification of the situation."

Read more: French CGT union threatens more protests

One of Macron's most trusted allies, Delevoye joined the cabinet in September after recommending in a report that the retirement age for claiming a full pension be raised by two years.

The proposal has been met with fierce opposition, resulting in a series of strikes, including by transport workers.

Unions warned that the government would be crossing a "red line" if it tinkered with the retirement age and urged their members to take part in a mass demonstration planned for Tuesday.

They demanded that Macron abandon his plans to create a single pensions system out of the existing 42 schemes.

Union chiefs argued the measure would delay the retirement of millions of people who were looking forward to a full pension.

Macron has so far shown no sign of backing down from what he describes as "a historic reform".