Serbian FA requests help to fight hooliganism
Karadzic said only a co-ordinated effort by the FSS, Serbia's government and its clubs could crush hooliganism after last month's warning by UEFA president Michel Platini that Serbia could be thrown out of Euro 2012 qualifiers.
"It is of utmost importance to adhere to UEFA's instructions because our national team and domestic clubs are in danger of being kicked out of international competition and this should be taken very seriously," Karadzic told a news conference.
"Platini's meeting with Serbia's president Boris Tadic last month made it clear that UEFA expects the government to tackle this burning issue.
"Unless the problem is dealt with swiftly and ruthlessly, with zero tolerance for hooliganism and the offenders, we risk heavy sanctions which would grind Serbia's international football to a halt," he said.
Karadzic's request came before Wednesday's Cup semi-final between bitter Belgrade rivals Partizan and Red Star, whose matches have a long history of crowd trouble.
The potentially explosive clash will be the first test for Serbia's authorities after the country's fans caused a riot during a Euro 2012 qualifier in Italy in October, forcing the match to be abandoned after six minutes.
Having attacked their own team bus before kick-off, Serbian fans threw flares at home fans, players and police and they clashed with riot police outside the stadium.
Italy were awarded a 3-0 walkover and Serbia were fined, ordered to play at least one home match behind closed doors and instructed to refrain from allocating any tickets for their remaining away games.
That incident followed a 2009 fatality, when Partizan ultras beat to death a French supporter before a Europa League match against Ligue 1 side Toulouse.
Serbia play their next Euro 2012 qualifier at home to Northern Ireland behind closed doors on March 25 and visit Estonia four days later.
They are fifth in Group C with four points from four games, six behind leaders Italy.