VALLETTA, MALTA -- Maltese minister Justyne Caruana resigned Monday after her husband, a former investigator into the murder of a prominent journalist, was revealed to have holidayed with the alleged mastermind behind the killing.

Caruana -- who was appointed to the government's brand-new cabinet just last week -- said in her resignation letter that she was quitting despite being "totally extraneous" to the affair, the prime minister's office said in a statement.

Her exit came after the Times of Malta said Sunday her husband, Silvio Valletta, travelled to a football match in Britain with tycoon Yorgen Fenech, who has been charged with complicity in the murder of Daphne Caruana Galizia.

Caruana had sworn in on Wednesday as minister for the island of Gozo under Malta's new leader Robert Abela.

She had held the same post under his predecessor, Joseph Muscat, who resigned over allegations he hampered the murder probe.

Valletta was deputy police commissioner at the time of blogger Caruana Galizia's 2017 car bomb murder. She had exposed high level corruption in the island state.

He suspended himself from the case in June 2018 after a court upheld a claim by the slain reporter's family that there was a conflict of interest, because of the investigator's ties to a minister in a government Caruana Galizia had frequented targeted.

That ruling was appealed by the attorney general, but upheld by the country's highest court in October 2018.

Valletta travelled to watch a football match at Chelsea FC's Stamford Bridge Stadium in September 2018, after suspending himself from the case but before the constitutional court's decision.

A video showing him in Fenech's Rolls Royce was found on the businessman's phone.

Fenech was charged as an accomplice in the murder after being detained trying to leave the country on his yacht.

His arrest in November sparked the resignation of Muscat's chief of staff and the tourism minister, before claiming Muscat's scalp as well.

Three men are on trial for allegedly detonating the bomb that killed the 53-year-old mother of three.

Valletta on Sunday admitted the holiday with Fenech, but said it only came once he had stepped aside from the case.

He said he paid for the flights himself, and he did not know Fenech was a suspect in the murder at the time.

"I never did anything wrong and would certainly never have gone abroad with anyone who I suspected or knew to be under investigation", Valletta, who retired from the police force in September, told journalists.

Malta's home affairs minister said Valletta's trip with Fenech will be investigated.

© Agence France-Presse