The resignation of one of British Prime Minister's most trusted allies leaves May struggling to navigate the final year of tortuous Brexit negotiations.
British Prime Minister Theresa May was left weakened by the resignation on Wednesday of her deputy Damian Green, the latest crack in her government as she faces tough Brexit talks.
Green agreed to step down as the first secretary of state after a probe into his conduct found he had acted dishonestly.
The departure of one of her closest aides is the result of an investigation into Green's conduct following newspaper allegations published last month.
The Sunday Times reported that pornography was found on his parliamentary computer in 2008, while a journalist claimed Green acted inappropriately towards her in 2015.
In its report, the Cabinet Office said Green had breached the ministerial code when he made "inaccurate and misleading" statements, by falsely claiming he was unaware that indecent material had been found on his computer.
Scandal at Westminster
In his resignation letter, Green apologised for breaching the ministerial code, while denying that he downloaded or viewed pornography in parliament.
He also expressed his regret at the "distress caused" to Maltby, who claimed Green touched her knee and later sent her a suggestive text message.
Green's resignation comes as part of a broader scandal over sexual harassment at Westminster, which erupted weeks ago and prompted the departure of Defence Secretary Michael Fallon last month.
Fallon's resignation was followed a week later by that of Britain's overseas aid minister, Priti Patel, who stepped down over unauthorised meetings in Israel.
The loss of two ministers in a matter of days cast doubt over May's authority, already challenged by divided opinions within her cabinet over Brexit.
May loses an important ally in Green, a former journalist who was first elected to parliament in 1997.
He rose through the ranks to become work and pensions secretary last year under May, before being appointed the first secretary of state after the June election.