Cardinal Cormac Murphy-O'Connor, the head of the Catholic Church in England and Wales, is facing increasing pressure to ban doctors from offering contraception or referring patients for abortions at a hospital in north London.

The cardinal is able to use his position as "arbiter of ethics" at the Hospital of St John and St Elizabeth, a private Catholic hospital in St John's Wood, to push through the implementation of a code of ethics which forbids any medical practices banned by the Vatican.

Campaigners now intend to appeal to Pope Benedict XVI to intervene directly if Cardinal Murphy-O'Connor does not implement the ban.

Nicolas Bellord, secretary of the Restituta Group, which is campaigning to preserve the hospital's Catholic identity, said: "We have not seen effective legal action from the cardinal on this issue. As the matter stands, the hospital is committed to a GP practice on the premises which will have a contractual agreement with the NHS to provide family planning services.

"We are looking to the cardinal to uphold the constitution of the hospital and the teachings of the Roman Catholic Church. If that does not happen then we will have no alternative but to seek to refer the matter to the Vatican and his Holiness the Pope."

The hospital has built a celebrity reputation with Cate Blanchett, Emma Thompson, Kate Moss and Sara Cox all giving birth there.

Two years ago it was alleged that some staff at the hospital were breaking its rules by referring patients for abortions. At that time Cardinal Murphy-O'Connor demanded that the hospital revise its existing code of ethics.

In a letter to the hospital's chairman, Lord Bridgeman, Cardinal Murphy-O'Connor wrote: "There must be clarity that the hospital, being a Catholic hospital with a distinct vision of what is truly in the interests of human persons, cannot offer its patients, non-Catholic or Catholic, the whole range of services routinely accepted by many in modern secular society as being in a patient's best interest."

However, the attempt to revise the hospital's code of ethics has upset a number of staff at the hospital, reports the Belfast Telegraph, with many unhappy at not being allowed to refer patients seeking an abortion to another hospital or to give advice on such issues.

The controversy continued earlier this year in May when the hospital's medical advisory committee wrote to the board telling them that it expected Cardinal Murphy-O'Connor to resign as a patron, saying the hospital should be a "non-Catholic hospital with a Catholic heritage".

It is thought that a new version of the code of ethics was referred back to the hospital board this month and could pass formal approval in the next few weeks.

Medical staff are requesting that they be allowed to operate under the guidelines of the General Medical Council, the medical profession's governing body. These guidelines require all clinicians to offer objective medical advice and referrals regardless of their personal or religious beliefs.

The hospital said this week that the revised code had been referred both to the GMC and the Nursing and Midwifery Council for approval.

In is thought that the new version of the code recognises the requirement for medical staff to abide by the GMC guidelines.

According to the Belfast Telegraph, a spokesman for the Srchbishop said: "The cardinal is actively engaged in finding a solution to these important issues. He sincerely hopes the board will make the right decision."