A Conservative MP failed to declare that she held shares valued at more than £70,000 in Shell while she was environment secretary.

Theresa Villiers admitted her shareholding in the oil and gas company via her latest update to the register of members’ financial interests.

Under the section “other shareholdings, valued at more than £70,000”, Ms Villiers’ entry says: “From 23 February 2018, Shell PLC; energy. (Registered 17 July 2023).”

Ms Villiers served in Boris Johnson’s cabinet as environment secretary from July 2019 until February 2020.

Theresa Villiers' entry to register of financial interests
A copy of the latest entry to the register of members’ financial interests from Conservative MP Theresa Villiers (PA)

MPs are required to register any change to their registrable interests within 28 days.

A list of ministers’ interests from November 2019 did not include a mention of the shares for Ms Villiers.

The MP for Chipping Barnet’s latest entry to the register also included newly declared shares above the same threshold in drinks manufacturer Diageo from February 23 2018 and Experian PLC from July 29 2019.

A spokesman for Ms Villiers told the Daily Mirror: “Ms Villiers deeply regrets her failure to monitor the value of shareholdings and has offered her sincere apologies.

“These shares are part of portfolio which is professionally managed for Ms Villiers and for which she has never taken day-to-day investment decisions.

“It did not occur to her that any single shareholding would reach the threshold for declaration, but a legacy received in 2018 caused that to happen.

“As soon as she realised this, she alerted the registrar of members’ interests and the standards commissioner. She takes full responsibility for the mistake.

“She accepts that it should never have happened, and that she should have kept track of the additions to her investment portfolio. She is taking steps to ensure that this never happens again.

“Nothing she has ever said or done as MP has been influenced by these shareholdings.”

The spokesman added to the Mirror: “When she was appointed as secretary of state, Ms Villiers disclosed to Defra (Department for Environment Food and Rural Affairs) that she had a portfolio of shares which was professionally managed for her and over which she did not take investment decisions.

“She offered to place this in a blind trust. The prime minister’s ethics adviser said that this step was unnecessary because the portfolio was managed for her and she did not take investment decisions. So ministerial code requirements were complied with.

“Nothing she did as Defra secretary was influenced by any of these shareholdings.”