The NHS's longest serving chief executive has allegedly been "pushed out" of his job after he attempted to suspend senior consultants who were part of a "sex ring" operating on hospital grounds.

Sir Leonard Fenwick, who has been chief executive of Newcastle and Tyne Hospital Trust since 1992 and managing hospitals in the area for 40 years, was put on "extended leave" from the hospital in January 2016.

No official reason has been given as to why he is on leave but the Daily Telegraph has reported that he had exposed a "sex ring" involving consultants who would meet female staff for sex on hospital premises or in a nearby hotel during working hours.

One anonymous hospital worker told the newspaper that married consultants "shared" female staff between them using code words such as "marmite" and "cappuccino" for sex sessions.

The staff member said one consultant met a female colleague at the Signature Sandman Hotel for sex during working hours and that they had "groped" each other in a patient environment.

It was stated that the group had sent "hundreds" of indecent emails and text messages during the work day with references to one female NHS worker as 'the Madam'.

The source said that an investigation by the Trust uncovered sordid emails sent between consultants to three female secretarial and clerical members of staff.

Upon discovery of the network, Fenwick, 69, from West Jesmond, in Newcastle, had moved to suspend the two consultants but the source said that chair, Kingsley Smith, and a non-executive director, Bryan Dodson, blocked the motion.

Instead the consultants were told they could keep their jobs after a disciplinary hearing, the source added, although the consultants have now reportedly resigned from their posts at the hospital.

Fenwick was responsible for one of the largest NHS trusts in the country with 15,550 staff and a budget of around a £1bn ($1.23bn) a year.

There has also been the allegation that the Trust's governors have been barred from speaking about Fenwick's "extended leave" or from contacting him.

Former governor and Trust member Paul Briggs told the Telegraph: "I have spoken to governors and they have been gagged" on the issue but affirmed that the CEO may have left after having differences with other members of senior management.

A spokeswoman for the Trust told the newspaper that they "strongly refute" the gagging allegations.

"The trust has been clear with staff and governors that Sir Leonard Fenwick is on a period of extended leave," she said.

"We have a duty to protect the confidentiality of all of our staff, and for that reasons we would not comment on his leave."