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Mayor Boris Johnson "screamed down the phone" at London's transport commissioner, angry that a section of a Tube line was shut for two hours earlier, sources at City Hall said.

The Jubilee Line was closed from London Bridge to Stratford from 0735 GMT by a broken-down train and a signal failure.

Mr Johnson had asked Peter Hendy "for a report on his desk by the end of the day", a spokesman for the mayor said.

Transport for London (TfL) has promised to refund passengers who were affected.

It apologised for "any inconvenience" and blamed a faulty train in the North Greenwich area which subsequently caused a problem with a signal.

"We're working hard to complete the upgrade of the Jubilee Line, which we're on track to do later this year," said London Underground's managing director, Mike Brown.

"The new signalling system is now in place and we're working to get on top of any issues with our suppliers right now."

The upgrade of the line's signals has been frequently delayed and was branded "a debacle" by Mr Johnson last February.

It is now scheduled to be completed this spring, five years after work began.

Bob Crow, the general secretary of the Rail, Maritime and Transport (RMT) union, said passengers had experienced "the worst week of chaos so far this year" on the underground network, with additional problems on the Metropolitan Line on Thursday and Friday.

The Tube system was failing "under the combined pressure of staffing and maintenance cuts and gross mismanagement right from the top", he added.

TfL said any Oyster pay-as-you-go passengers who had been charged for "incomplete" journeys on the affected stretch of the Jubilee Line between 0715 and 1030 GMT would be automatically refunded.

Any passengers with Travelcards or paper tickets could apply for refunds on the TfL website, it added.

Tube commuters hit by 'rush hour from hell'

Commuters suffered the "rush hour from hell" because of fresh delays to services, a union leader has said.

The Waterloo and City Line was suspended, signal failure disrupted the Victoria Line and the Jubilee Line was hit again by disruption on Monday.

It followed delays to the Jubilee Line on Friday when a section was shut for two hours.

The Rail Maritime and Transport (RMT) union said the Tube had become a "sick joke" that was failing passengers.

Bob Crow, RMT general secretary, added commuters had suffered the "rush hour from hell".

Transport for London said Monday's Jubilee Line delays were caused by signal failures at St John's Wood and Dollis Hill.

Mayor Boris Johnson was reported to have demanded an immediate report from his transport commissioner, Peter Hendy, following Friday's disruption.

Kulveer Ranger, the mayor of London's transport adviser, said: "The mayor has been assured that the upgrade of the Jubilee Line will be complete by the spring. He shares the frustration of Londoners affected by Tube problems this morning. He is overseeing the biggest upgrade in the Tube's history at the same time as it is carrying record numbers of people."

Ken Livingstone, Labour's mayoral candidate, said: "This morning's severe delays across the Tube network have once again caused huge frustration for millions of commuters. Boris Johnson's failure to get a grip of the daily delays, closures and disruption on the Tube shows he is increasingly out of touch with the issues of concern to ordinary Londoners."

Unions are locked in a bitter row with London Underground over hundreds of job losses at ticket offices which led to a series of strikes last year and remains unresolved.