Image caption Liam Fox resigned following revelations about his working relationship with Adam Werritty

Ministers are to consult on plans for a register of lobbyists according to government sources.

It comes after Liam Fox quit as defence secretary for allowing "distinctions to be blurred" between his professional role and friendship with Adam Werritty.

Foreign Secretary William Hague told the BBC "legitimate questions" had been raised about political lobbying.

Labour has urged the government to introduce a compulsory register of lobbyists "as a matter of urgency".

Speaking on BBC One's Andrew Marr Show, Mr Hague said he expected the prime minister to take stock once the cabinet secretary's report into Mr Fox's conduct was published on Tuesday.

He added that the prime minister would then consider what action to take, in particular over the role of lobbyists.

The BBC News Channel's chief political correspondent, Norman Smith, said ministers are to consult on the plans by the end of the year with legislation being introduced next year.

'Greater transparency'

The register was a policy of the coalition agreement which states: "We will regulate lobbying through introducing a statutory register of lobbyists and ensuring greater transparency."

Labour's shadow cabinet office minister Gareth Thomas said: "David Cameron has still not introduced the compulsory register of lobbyists he promised.

"In the wake of the Adam Werritty and Atlantic Bridge activities it is now essential we have greater transparency.

"The government should bring forward as a matter of urgency plans for a compulsory register of lobbyists with records being kept of meetings between lobbyists and ministers."

'Virtue of openness'

International Development Secretary Andrew Mitchell said the prime minister and the cabinet secretary would look at what lessons could be learned.

Mr Cameron was committed to "cleaning up politics," he told Sky News's Murnaghan programme, adding: "We make a virtue of openness."

Shadow Defence Secretary Jim Murphy has called for a wider inquiry, once the initial report is published.

Image caption An inquiry into Mr Fox's conduct is due to publish its findings on Tuesday

"It's now clear that there are much wider issues at stake: access to money; access to influence; money off the books; money undeclared influence. And I think what we need to do is follow the money trail and see where it leads us," he told BBC One's Politics Show.

Politicians from all parties have, over the years, called for action to be taken on lobbyists, according to our correspondent.

Successive inquiries into the regulating lobbyists at Westminster go back to 1983.

In 2009 the Public Administration Committee called for a statutory register, which would include a list of all lobbyists, their clients and a diary of all meetings with "decision makers."

In June, the European Union introduced a voluntary Transparency Register for lobbyists to sign up to as part of plans to show who is involved at influencing the EU decision-making process.

Meanwhile, the City of London police are considering whether to investigate Mr Werritty for fraud for using business cards falsely claiming he was an adviser to Mr Fox.

Mr Fox resigned from his cabinet post on Friday after a week of damaging headlines over his working relationship with Mr Werritty, his former flatmate and best man.

It emerged that Mr Werritty had met Mr Fox 22 times at the Ministry of Defence and joined him on 18 overseas trips since he came to office last year - despite having no official role.

Mr Werritty was present at meetings Mr Fox had with military figures, diplomats and defence contractors.