PARIS, April 3 (Reuters) - Paris St Germain and Olympique Marseille have been docked a point each over a row involving a Ligue 1 meeting between the two arch-rivals last month.
The ethics commission of the French Football Federation (FFF), meeting in Paris on Monday, ruled that the clubs had harmed the sport's image.
Both clubs said they would appeal against the ruling.
The FFF also said that the clubs' presidents, PSG's Pierre Blayau and Marseille's Pape Diouf, would be suspended for three months.
The clubs must also sign before June 30 an agreement to ensure further incidents do not occur or face the prospect of playing each other behind closed doors, the FFF said in a statement.
'This is an astounding decision,' Marseille said in a statement. 'The club intends to use every existing means (to fight the ruling).'
PSG said in a statement they would also lodge an appeal.
Marseille, fearful for the security of their fans and players at the Parc des Princes, had sent their B team to Paris for the match on March 5 and asked their supporters not to travel to the capital. The game was a 0-0 draw.
Marseille had accused PSG of refusing to sell them the promised number of tickets and of seating Marseille fans just underneath PSG supporters.
LFP president Frederic Thiriez had urged Marseille to send their best team to Paris, saying every possible measure had been taken to guarantee maximum safety.
Marseille lie seventh in Ligue 1, 20 points behind leaders Olympique Lyon and two points ahead of eighth-placed PSG. The point deduction will not affect the teams' rankings but will make it harder for them to qualify for Europe.
Matches between PSG and OM are always regarded as high risk. Security was particularly tight for last month's game after rival groups of PSG supporters had fought each other and ransacked a motorway service station on their way back from a match the previous weekend.
The game, which was due to kick off at 2000 GMT, was brought forward four hours to help security forces.
The 48,000 spectators were searched and some 1,200 policemen were deployed around the stadium whose surroundings were open only to ticket-holders.
A Marseille supporter was paralysed after being hit by a seat thrown by PSG hooligans during a game between the two rivals at Parc des Princes in 2002.
'Those who love football are tired of the deplorable show those two teams offer every time they meet,' Thiriez said during last month's row. 'That's enough'.