ATHENS, Greece - Greece is facing a FIFA ban over a government decision to suspend the country's cup competition because of fan violence.

Sports Minister Stavros Kontonis called off the Greek Cup last month following violence at a semifinal match between PAOK and league champion Olympiakos. PAOK fans threw flares and clashed with riot police on the field.

In a letter to Kontonis on Tuesday, FIFA described the action as "disproportionate and as interference in the internal affairs" of the Greek soccer association, and issued a 10-day deadline to reverse the decision.

A suspension would see Greece's national teams, clubs and referees left out of all international competitions.

"Less stringent or more appropriate measures, such as matches without spectators or international refereeing for the remaining games of the Greek Cup could have been implemented," the letter said.

The issue has been complicated by a legal challenge launched against the government by the Greek soccer association, which had been due to be heard at a high court Tuesday. The hearing was postponed until April 19 because of a lawyers' strike.

Greece's 15-month-old leftwing government says it is determined to clean up what it describes as decades of corruption and violence in Greek soccer — a message Kontonis conveyed to a FIFA delegation which visited Athens last week.

After that visit, Prime Minister Alexis Tsipras met his sports minister and said in a post on Twitter: "I asked him not to take one step backward. Everyone must accept the cleanup (of Greek soccer) or face the consequences."