Authorities in Libya have banned its national sports teams from competing against Algeria and Egypt.
Libyan football teams must also request state authorisation before playing teams from other Arab countries.
The authorisation is required to ensure "good sportsmanship", but no reason was given for the Algeria and Egypt ban.
But the BBC's Rana Jawad in Libya says many believe the ban is linked to last year's violence at a World Cup play-off match between Algeria and Egypt.
The new regulations were outlined in a letter dated 25 May, which was made available to the media on Wednesday.
A source at the Libyan Football Federation told the BBC that he hoped the measures would be reversed by the time Libya hosts the Africa Cup of Nations in 2013.
Last November, the Algerian team bus was pelted with stones before a World Cup qualifying match with Egypt.
The subsequent play-off match between the two countries for a place in the World Cup in South Africa was moved to the more neutral setting of Sudan, but each side accused the other's fans of attacking their supporters.
Algeria won the play-off.
Relations between Algeria and Egypt have deteriorated since the controversial World Cup games.