Fresh strikes by security guards at Heathrow airport are expected to be announced next week.
Members of Unite are embroiled in a long-running dispute over pay which has led to previous industrial action.
In a statement, Unite said: “The Unite notice regarding the industrial action at Heathrow is not live.
“It should be held at the moment until notice is served on the employer, next week.”
A Heathrow spokesperson said: “Passengers can rest assured that we will do everything we can to minimise strike disruption so they can enjoy their hard-earned summer holidays.
“Unite has already tried and failed to disrupt the airport with unnecessary strikes on some of our busiest days and we continue to build our plans to protect journeys during any future action.
“The simple fact remains that the majority of colleagues do not support Unite’s strikes.
“There is a two-year inflation-beating pay rise ready for colleagues, if only Unite would allow them to have a say.
“We will continue talks with Unite about resolving this issue.”
Last week security guards at Heathrow completed a three-day strike in the dispute over pay.
Members of Unite had previously held 15 days of strike action, including over the busy Easter period.
On 31 March, hundreds of security officers in the union who work for Heathrow completed 10 days of strikes.
The action involved guards at Terminal 5, which is only used by British Airways, and those who check plane cargo.
