A proposed two-day strike at Heathrow Airport has been put on hold, allowing more time for negotiations.

The last-minute reprieve still saw flights in and out of the airport cancelled – causing school holiday misery for thousands of travellers.

And, despite the “time-out” for further talks, Unite union workers plan to walk out tomorrow (Tuesday).

Both sides spent the weekend in talks monitored by the conciliation service Acas.

The announcement that today’s action would be stopped came late in the evening.

Unite said: “The strike by Unite members working for Heathrow Airport has been suspended to allow for further talks at Acas.

“Under the chairmanship of the conciliation service Acas, tomorrow’s talks will involve senior directors from Heathrow Airport and senior Unite officials with the aim of averting a second day of planned strike action set to start at 00:01 and finish at 23:59 on Tuesday 6 August.

“Unite will not be making any further comment while talks are ongoing.”

Heathrow had already cancelled more than 170 flights scheduled for Monday and Tuesday.

A Heathrow spokesman said: “We will continue talks with Unite tomorrow and we remain hopeful that we can find a resolution and stop this disruptive and unnecessary threat of strike action.

“Airlines may choose to reinstate impacted flights.

“We regret that passengers have been inconvenienced by this and urge them to contact their airline for up to date information on the status of their service.

“On Tuesday’s planned strike, Heathrow said it has been working closely with airlines to identify departing flights which will need to be cancelled.

“While the vast majority of flights will be unaffected, some airlines are making arrangements to operate flights from other UK airports, others will be delaying flights and unfortunately a number will be cancelled.

“Airlines have now started to contact passengers on affected flights and passengers should contact their airline for more information.

“We recommend passengers check their flight status before travelling to the airport and read the guidance on http://heathrow.com/ to prepare for their journey.”