Tui has extended holiday cancellations to Sri Lanka until July 18.
The move came as the Foreign, Commonwealth & Development Office reinstated advice against all but essential travel to the strife-torn Indian Ocean island.
The FCDO warned of a “severe economic crisis” in Sri Lanka.
Tui initially withdrew its Sri Lanka programme until the end of May before extending it throughout June.
The latest extension of the suspension was blamed on the ongoing political and economic instability in Sri Lanka.
Tui said: “As a result, we’ve unfortunately had to cancel all holidays to Sri Lanka departing up to and including 18 July 2022.
“We will be proactively contacting all impacted customers in departure date order to discuss their options.
“Please note this advice does not apply to customers transiting through Sri Lanka’s international airport and customers currently in resort can continue to enjoy their holiday as planned.
“We will continue to monitor the situation and update customers should there be any further updates.”