The move comes after Tui further extended its suspension of holidays to the island. The operator pinned the latest round of cancellations on the "ongoing political and economic instability" in the country.
Despite the easing of travel restrictions, the FCDO still warned Sri Lanka is experiencing a "severe economic crisis" which has led to a shortage of basic necessities.
"The major shortage of fuel (diesel and petrol) is affecting transport, businesses, and emergency services," the FCDO’s advice states. "Hospitals and other medical services such as ambulances may be affected by shortages.
"There are daily power cuts due to electricity rationing. It is more important than ever to get appropriate travel insurance and check it provides sufficient cover."
It further warned that protests about the economic situation have led to violence against peaceful protesters in recent months, resulting in injuries and loss of life.
"Tear gas and water cannons have been used to disperse protesters," it continued. "Protests, demonstrations, roadblocks and violent unrest could occur at short notice. Curfews and emergency regulations may also be imposed."