Cambodia has taken over the running of the country’s Thai-owned air traffic control firm, in a deepening row between the two neighbouring countries.
Cambodia also barred all Thai employees from turning up for work and put a Cambodian national in temporary charge.
The move comes a day after a Thai engineer working for the firm in Phnom Penh was formally charged with spying.
It is said he passed on details of last week’s flight to Cambodia by former Thai Prime Minister Thaksin Shinawatra.
Mr Thaksin, who is wanted in Thailand to serve a jail sentence for corruption, spent five days in Cambodia in his new role as an economic adviser.