LUANDA (Reuters) – Emirates airline has scaled back its five weekly flights to the Angolan capital Luanda to three due to the difficulty of repatriating revenue earned in the country, the president of the Middle East’s largest airline said.

“As I have previously indicated, the viability of our operations in Luanda is being severely impacted by limitations on the repatriation of out sale proceeds being accumulated in Angola on a daily basis,” Timothy Clark said in letter dated July 9 to Angola’s transport minister Augusto da Silva Tomas.

Hit by a collapse in the price of crude oil, Africa’s second largest oil exporter has been depleting its reserves at a faster rate to fund imports and pay down government debt, and imposed capital restrictions including amounts travellers can take abroad.

Clark said the limitation on flights, which came into effect on Sunday, would also come under review very quickly if significant progress on the moving its funds out of the country was not made in the coming days.

The Gulf airline also terminated a deal with Angolan airline TAAG, under which Emirates took operational control of the airline for 10 years and the two cooperated on commercial opportunities on the continent. The agreement was signed in 2014.