The completion of work to upgrade the Jubilee Line has been delayed until 2010 Anna Branthwaite

PASSENGERS face more Tube woe after it emerged that weekend closures on the Jubilee line could last until well into 2010.

Transport chiefs admitted there were “grave doubts” over whether the £500m upgrade of the busy line would be completed by Christmas.

Underground maintenance company Tube Lines and contractor Bechtel have closed the line every weekend this year, wreaking havoc on millions of journeys.

The work has badly affected The O2, with Beyoncé and Madonna fans complaining of six-hour journeys to get home after concerts.

Another 12 weekend shutdowns are planned before the end of December, but Tube Lines is demanding even more to get the work done.

A report from London Underground today cast doubt on whether the work would be completed this year.

Managing director Richard Parry said: “Regrettably we now harbour grave doubts over Tube Lines’ and Bechtel’s ability to deliver the upgrade of the Jubilee line by the end of December, which they are contracted to do.”

"Tube Lines must get its act together if Londoners are to benefit from faster, more frequent and reliable services on the Jubilee line"

Calling for an independent review, he accused the companies of failing to keep them informed, saying: “We no longer have any confidence in what they are telling us. ”

Boris Johnson blasted the delays and said the work had “stretched the patience of Londoners and business almost to breaking point”.

The Mayor added: “Tube Lines must get its act together. I am hugely frustrated at their progress, it is unacceptable.”

Jo DeBank, of London Travel Watch, said: “Sadly it means more suffering for poor old Jubilee line passengers.”

Tube Lines, which posted a £73m pre-tax profit in 2007/8, originally said it would have the work finished by June.

Today a spokeswoman said the firm believed it would finish the upgrade this year.

The work is set to increase the line’s capacity by a third.