It has emerged that a fifth claim of “inappropriate behaviour” towards a male priest has been made against Cardinal Keith O’Brien.

The 74-year-old, who denied the first set of allegations last weekend, resigned as leader of the Scottish Catholic Church on Monday.

He was due to retire this month but the resignation was brought forward.

The allegations surfaced last Saturday one day after Cardinal O’Brien told the BBC that male priests within the Catholic Church should be able to marry female partners.

The cardinal’s progressive stance on heterosexual matrimony ran counter to his views on LGBT equality.

Last November, Cardinal O’Brien was named ‘Bigot of the Year’ by a gay rights charity due to his staunch opposition to marriage equality.

In 2012, he stated that same-sex relationships were “harmful to the physical, mental and spiritual wellbeing” and compared equal marriage to slavery and child abuse.

In an editorial on Friday, British Catholic newspaper The Tablet said: “When Cardinal Keith O’Brien called gay marriage a ‘grotesque subversion’ and ‘madness’ it attracted widespread censure. No wonder the accusations of inappropriate behaviour as a younger man – strenuously denied – were so damning. If true, it made him look a hypocrite. For the church this was a public relations disaster.”

Meanwhile, the Scotsman newspaper reports that the resignation of Cardinal Keith O’Brien was triggered by a claim of inappropriate behaviour towards a priest in 2001 that was lodged with the Vatican in October.

It is the fifth such allegation to be made public and also the most recent – allegations in the Observer dated back to the 1980s.

The complaint is said to have given other men confidence to come forward with allegations against the cardinal.