Egyptian authorities have barred the chief executive of Orascom Construction Industries, one of the country's biggest companies, from leaving the country as part of an investigation into tax evasion, state media said on Sunday.

The public prosecutor ordered that OCI chief executive Nassef Sawiris and his father Onsi Sawiris be barred from travel, the state news agency Mena said.

The order from the public prosecutor is part of an investigation into accusations they evaded about 14 billion Egyptian pounds ($2.1 billion) of taxes during the sale of Orascom Building, an OCI subsidiary, to French firm Lafarge, Mena said.

Reuters could not reach either Sawiris for comment, and an official from Orascom was not immediately available.

A banker and friend of the family said the men were out of the country. Under the order, they would be detained on arrival if they returned.

A lawyer for OCI, Hani Sarie el-Din, told state-owned newspaper Al-Ahram he was "surprised" by the decision.

Negotiations about the taxes from the deal were continuing, the paper's website quoted him as saying. "There was nothing suggesting a dead end in the negotiations."

Last week an official said the government was holding talks with OCI to dissuade it from delisting from the local stock exchange.

Last January the Dutch-listed parent, fertilizer and construction firm OCI NV announced an offer to acquire the ordinary shares of its Egyptian-listed subsidiary.

The Egyptian Financial Supervisory Authority (Efsa) asked last month for more information on the offer, a move that could delay completion of the deal under which some US investors including Bill Gates would pay shareholders who choose to sell their ordinary, Egyptian-listed shares. – Reuters