MPs have called for the power to jail people who lie to parliament as they step up their attack on the cover- up over phone hacking.

Fines should also be imposed on those who commit contempt, Labour MP Chris Bryant said.

The call came as parliamentarians asked the Commons standards watchdog to examine claims that three former News International executives misled an influential committee.

Former News of the World editor Colin Myler, the paper's former legal manager Tom Crone and one-time News International executive chairman Les Hinton, have denied the allegations.

As it stands potential sanctions for contempt include being summoned to the Commons for a public dressing-down. But Mr Bryant called for those to be bolstered to recognise how serious it was if MPs were being "hoodwinked."

Rupert Murdoch has admitted there was a cover- up over phone hacking, but said he had known nothing of it at the time.

Yesterday's move was widely viewed as a rubuff to Lord Justice Leveson, who has called on Parliament not to interfere with his public inquiry into phone hacking at the now defunct News of the World.

Earlier this month he warned parliament to delay publication of papers surrounding Culture Secretary Jeremy's Hunts handling of News Corp's takeover bid for BSkyB.

The Coalition Government faces more potential embarrassment at the Leveson Inquiry tomorrow, where it will hear evidence from Adam Smith, Mr Hunt's former special adviser. Mr Smith resigned last month after admitting that he had overstepped the mark in his dealings with Murdoch executives.

Mr Hunt has consistently denied improper behaviour. He said he will be vindicated when he is called before the Leveson inquiry.