The Catholic Church is on a collision course with the Scottish Government over planned anti-sectarianism legislation after calls by one of Scotland's leading churchmen for it to be delayed.

Philip Tartaglia, the Bishop of Paisley, has launched an unprecedented attack on the SNP administration amid claims of a “serious chill in relations” between ministers and the Catholic hierarchy and accusations it distracts “from the real nature of sectarianism”.

He has written to Alex Salmond accusing him of reneging on pledges to make public statistics on convictions for sectarian offences, claiming the Government was rushing headlong into laws without first revealing the full extent of the problem.

Bishop Tartaglia, who is tipped by many observers to be the next Scottish cardinal, said the consultation on the Offensive Behaviour at Football Bill threatened to undermine the First Minister’s efforts to embrace Catholics, adding there was already a “growing apprehension and disappointment at the direction your Government is taking” among members of the faith.

Scotland’s leading historian and authority on sectarianism last night demanded an apology from the Lord Advocate, Frank Mulholland, for his handling of the affair.

Tom Devine, senior research professor in history at Edinburgh University, also told The Herald the Catholic Church had been deceived and the academic community left disappointed.

In the bishop’s letter, which signals a major rupture between the SNP and many Scots Catholics, the churchman talks of being “perplexed” at a number of actions by ministers.

This includes Justice Secretary Kenny MacAskill’s praise of fans for their behaviour at the League Cup Final between Rangers and Celtic in March, despite the sectarian anthem The Billy Boys being audible to television viewers. He also referred to comments by Community Safety Minister Roseanna Cunningham about the use of the sign of the cross.

Sources within the Catholic Church claim the letter is the result of a build-up of frustrations with SNP ministers. They say the bill flies in the face of attempting to build a national consensus on matters such as religious hate crimes and could nullify the appetite for independence among Catholics.

Claiming he had previously supported the “good intentions” of the bill, the bishop adds: “Along with many, I am also concerned the bill’s introduction has served as a distraction from the real nature of sectarianism in Scotland. Official figures made available some years ago show conclusively sectarian criminality is made up predominantly of acts of intolerance and hostility towards Catholics. We know several years’ worth of subsequent data on sectarian offences remains locked in the vaults of the Crown Office.

“It is disappointing that, despite repeated requests from the Catholic Church and from others for this data to be made public, and despite assurances from you and your Government that it would be, your officials have decided to shelve plans to release that information. Instead, what we appear to have is an indecently hasty desire to enact legislation to deal with a problem the core of which your Government steadfastly refuses to name or measure.”

He adds: “I hope you will delay the passage of the bill to permit a thorough examination of the available data.”

The letter, which The Herald has seen, also criticises the consultation on same-sex marriage. It talks of “serious misgivings about plans to dismantle the definition of marriage in Scotland” and says “your apparent commitment to such a course, will, I fear, bring about a serious chill to relations between the Scottish Government and the Catholic Bishops’ Conference”.

It concludes with criticism of the SNP’s efforts at being a Government of national unity which would “move forward towards an independent Scotland by respecting and developing the historic foundational values of faith and reason which have contributed to making Scotland a nation”, adding: “For that reason, I would be very sorry if you began to lose the confidence of the Catholic community.”

Professor Devine said: “The position taken by the Roman Catholic Church on this squares with my own recollection of what was promised, that it would be a full-scale, statistical analysis of all the data, comprehensively transparent, from 2003 to the present, and that work would start on it

immediately. We now find out it is going to be yet another year’s snapshot and work on the project has not even begun.”

A spokesman for Mr Salmond said: “The Scottish Government is conducting a consultation on same-sex marriage, and no decisions have been arrived at – there are clearly different views and an honest disagreement on this particular issue, and the Catholic Church and other organisations have every right to express their position. The work to publish the analysis of religious aggravation charges for the most recent year, 2010/11, has been under way for some time, and will be published next month as pledged”