David Cameron will express his regret this week over the mistakes which led to the deaths of 96 Liverpool fans at Hillsborough in 1989, but he has not yet committed himself to making a public apology for the disaster.

The Prime Minister will offer an "expression of regret" over the handling of the tragedy, after the publication of an independent report into the events before, during and after the fatal crush at the FA Cup semi-final between Liverpool and Nottingham Forest.

Mr Cameron has not yet seen the report, compiled by the Hillsborough Independent Panel, chaired by the Bishop of Liverpool, the Right Reverend James Jones. But senior government sources stressed that he was ready to issue a full apology if the report, and more than half a million pages of documents relating to the disaster, reveal failings on the part of the police, government or other public bodies.

"A lot of people have concerns about the police, but we expect the report will contain legitimate criticism of the way the government handled things at the time," a government source said. "We haven't seen the report yet, but the tone of the response is going to be in the direction of an expression of regret."

Last October, Mr Cameron told the Commons that Hillsborough was "a national tragedy".

He added: "I am hugely sympathetic to the families of the victims, and I am sure that there are regrets for all the institutions involved at the time, including the Government."

In 1990, an inquiry chaired by Lord Justice Taylor ruled the prime cause of the catastrophe was mismanagement by South Yorkshire Police, who allowed overcrowding on the terraces at Sheffield Wednesday's Hillsborough ground.

But relatives of the victims have complained that the police attempted to shift the blame on to Liverpool fans, claiming that many of them caused the crush after arriving drunk, late and without tickets.

Documents released earlier this year disclosed that the then-prime minister, Margaret Thatcher, was told a senior police officer had blamed "drunken Liverpool fans" for causing the disaster.

The Jones report is expected to reinforce condemnation of the police, although it may go further and criticise the response of politicians who assumed hooliganism played a part.

Campaigners insist the injustices faced by the victims' families over the past two decades mean Mr Cameron should offer a full public apology for the "cover-up" when the report is published on Wednesday.

Margaret Aspinall, chair of the Hillsborough Family Support Group, said the Prime Minister's response should mirror his apology after the Saville Inquiry laid bare official failings over the Bloody Sunday killings in Londonderry in 1972.