Former Conservative defense secretary Sir Grant Shapps has resigned from his position at a leading aerospace company due to concerns over potential breaches of regulations regarding employment for former government ministers.

Shapps, 57, who served in various roles in the cabinets of Cameron, Johnson, Truss, and Sunak, stepped down as chair of Cambridge Aerospace on April 30. This move came after the firm secured a lucrative government contract for missile systems.

Previously, Shapps, who was a defense minister under Rishi Sunak, had asserted that his involvement with the company was solely related to civilian aerospace activities. However, it later emerged that the company’s focus had shifted significantly towards defense projects.

New correspondence released on Tuesday between Shapps and the Advisory Committee on Business Appointments (ACOBA) revealed that Sir Laurie Magnus, the Independent Adviser on Ministerial Standards, had cautioned Shapps to rectify public representations, including on his LinkedIn profile, which indicated his leadership role in a defense-oriented company.

According to rules governing business appointments, former ministers are prohibited from lobbying the government for two years after leaving office and are required to seek guidance from ACOBA before accepting external employment opportunities.

In a letter dated May 12, Shapps acknowledged that the geopolitical landscape had evolved since the company’s establishment in 2024, especially citing developments in Iran. This change had blurred the distinction between military and civilian aerospace sectors.

While expressing regret, Shapps admitted that he should have sought updated advice from ACOBA as the company’s activities evolved. He emphasized that he had no direct involvement in securing the Ministry of Defence contract and only had limited awareness of the process.

Shapps maintained that he never exploited confidential information from his time in government, refrained from influencing policy through his connections, and did not engage in lobbying activities.

Sir Laurie Magnus, in a communication on May 19, criticized Shapps for allowing the perception of impropriety to develop by not seeking updated advice on his shifting responsibilities and for failing to amend public information about his association with Cambridge Aerospace.

Shapps, who previously represented Welwyn Hatfield as a Conservative MP, lost his seat to Labour’s Andrew Lewin in the recent General Election.