AN outspoken Australian churchman tipped as the potential next Pope has called on Scotland's Catholics to forge closer links with other faiths around issues such as same-sex marriage.

On his first visit to Scotland, Cardinal George Pell – one of the most influential figures in the Catholic Church and Pope Benedict's closest ally in the English-speaking world – said Jewish and Muslim communities were deeply concerned by the rise of aggressive secularism, citing attempts to redefine marriage.

A former Australian Rules footballer, the orthodox cleric is considered to be the most prominent churchman in Australian history.

He said the Church needed secular allies, and that many across the world respected "its commitment to serving the poor and its contribution to education, healthcare and human dignity".

Cardinal Pell, the Archbishop of Sydney, will be joined at the Year of Faith conference in Glasgow today by Professor George Weigel, a confidant of Pope John Paul II, who advised the late pontiff in the aftermath of the fall of the Iron Curtain.

Ahead of the conference, Cardinal Pell said: "We should seek to build upon our common ground with our brothers in faith in areas such as the defence of marriage and the family. The Jewish and Muslim communities are also concerned by the rise of aggressive secularism – in particular, its attempts to redefine marriage and impose a new orthodoxy on the culture, the aim of which is to silence traditional believers and force them to depart from the public square.

"We need secular allies also, especially civil and political leaders. Even in these troubled times, there remains an enduring respect and admiration for the Church because of its commitment to serving the poor and its contribution to education, healthcare and human dignity. This compassion is the practical and public expression of a Catholicism that is free to practise, to grow, to teach and to evangelise."

He said the Catholic Church "provides one-quarter of the world's healthcare, is the largest non-government provider of education in the world, and, through its Caritas network, distributes $2.6 billion (£1.6bn) annually in aid to the poor".

Cardinal Pell would only be the second English-speaking Pope after Pope Adrian IV in 1154.

A supporter of Australian republicanism and opponent of the detention of asylum seekers and the Iraq war, Cardinal Pell is considered a divisive character who is rarely far from the media spotlight.

He is morally conservative and stepped aside in 2002 after allegations he had abused a boy in the 1960s but was cleared. Observers said he emerged stronger following the allegations.

A devout follower of Pope Benedict's approach to the Church, his supporters say he would offer continuity as a successor to the current pontiff, with his role selecting bishops throughout the world considered a platform for the top job.

The Archbishop of Glasgow, Philip Tartaglia, said: "Cardinal Pell has been a hugely influential figure in Australian society and a powerful voice in the English-speaking Catholic world for more than a decade. The fact he is so willing to come to Scotland is for me a sign of hope, a sign the Catholic Church in Scotland is open for business, confident and prepared for a new effort to re-evangelise our society and culture."

Sources have told The Herald that inviting figures as outspoken and often controversial as Cardinal Pell would not have happened in Scotland under the previous and outgoing regime of bishops "who liked to keep their heads down and get on with things quietly".