The Public and Commercial Services union (PCS) has called for an inquiry into bullying in the civil service following multiple accusations against cabinet minister Priti Patel.

The union call came after the home secretary was accused of bullying staff at a third government department.

The latest claims are from her time as international development secretary from 2016 to 2017, and follow similar claims at the Home Office and the Department for Work and Pensions (DWP). It was revealed this week that a DWP official received a £25,000 payout after alleging she was bullied by Priti Patel in 2015 during her time as employment minister.

The DWP official claimed she attempted suicide as a result.

The DWP did not admit liability and the case did not go before a tribunal.

The issue came to public attention after bullying allegations against Ms Patel by Sir Philip Rutnam, who resigned as Home Office permanent secretary last week. He indicated he intends to take his former employer to an employment tribunal, claiming constructive dismissal.

PCS general Secretary Mark Serwotka said: “This government has presided over a bullying culture within the civil service which they have failed to tackle.” He added: “There should be an independent inquiry into bullying in the civil service. Our union along with others have been working with the cabinet office arguing for a clear procedure on handling complaints of bullying, discrimination and harassment, particularly regarding allegations against ministers, MPs and special advisers.” The union leader said: “Despite assurances that this would become part of the ministerial code, this appears to have been abandoned.”