The boss of Heathrow airport on Tuesday made a last-minute plea to staff urging them to avoid looming strikes that could cause summer disruption.

Europe’s busiest airport, which reported half-year results, is braced for industrial action, starting this Friday when as many as 4000 workers, including security guards and engineers, could strike over pay.

Boss John Holland-Kaye told the Standard: “I would urge the union to keep meeting with us ahead of the planned industrial action from Friday, and I would urge staff to come into work: we have a good deal on the table.”

Staff potentially walking out this week rejected an 18-month pay offer amounting to 2.7%, which according to union Unite amounts to just £3.75 extra a day for the lowest-paid workers in the dispute.

Holland-Kaye said the airport already pays well. He added: “If the action does go ahead the airport will stay open, and use contingency plans to ensure as many people can get on their holidays as planned. We will do our best to make disruption as limited as possible.”

He made the comments as Heathrow, which hopes to build a third runway, said passenger numbers rose 1.8% to 38.8 million in the six months to June 30. That helped lift revenues 4% to £1.5 billion.

Heathrow upped its operating costs by 4.1% to £580 million during the period, spending on security and upgrading drone defence technology. It plans to significantly increase investments into the airport from £600 million per year to £2 billion annually by 2022.

That will be used for automation, continual building refurbishments, and other upgrades.

On Brexit, Holland-Kaye said he would like to see some clarity soon.