UNIONS suspended planned strikes over the introduction of all-night Tube services yesterday, after bosses finally agreed to introduce a four-day working week.

London Mayor Boris Johnson aimed to launch overnight running on the Piccadilly, Victoria, Jubilee and Central lines last September, but the plan was postponed after he antagonised the workforce.

Unions brought London to a standstill with two all-out strikes last summer, saying new rosters would harm the staff’s work-life balance.

But after putting three further strikes on the calendar earlier this month, unions have now indicated they could reach a deal with bosses on the issue.

Rail unions Aslef, TSSA and Unite suspended their action yesterday. The RMT executive will meet on Monday to discuss the question.

The new deal includes above-inflation pay rises and a £500 lump sum for workers on lines affected by the night services.

Most significantly, bosses have agreed to a trial of a 36-hour, four-day week for drivers on the Jubilee line, with a view to introducing it elsewhere.

The executive of drivers’ union Aslef agreed a report from Tube organiser Finn Brennan proposing that the strikes be called off before members vote on the deal.

"The determination of our members brought London Underground management back to the table," Mr Brennan said.

"We have dragged them kicking and screaming into the 21st century with an agreement to deliver modern, flexible working patterns for our members and an above-inflation pay rise.

"This demonstrates just what strong, progressive trade unions can deliver in Britain today."