The United Nations tribunal prosecuting key suspects in Rwanda's 1994 genocide says it is facing serious financial difficulties because U.N. member states are delaying the payment of their pledges.

A spokesman for the International Criminal Tribunal for Rwanda, Roland Amoussouga, says the delay of payments from about 140 U.N. member countries has put the court, "into a serious financial situation."

Mr. Amoussouga says $212 million were pledged for 2004 and 2005, but less than a quarter of that has actually been paid.

"The member states have paid for the first six months, January to June. In order for us to operate, we have to have money," he said. "And because the money was not coming in, it became a great concern to us."

Mr. Amoussouga calls the delay in payments a habit of member countries that most U.N. offices have to contend with.

He says, in the past, the tribunal was able to borrow from the peacekeeping operations, but that's no longer possible under U.N.'s new budgetary regulations.

He says U.N. officials are meeting with member states to urge them to make their payments soon.

Mr. Amoussouga says he is confident the court will get its funding.

"The member states have support[ed] us very much, and they have political commitment," he added.

The tribunal was set up following the killing of as many as 800,000 Tutsis and moderate Hutus by Hutu extremists 10 years ago.

The court is supposed to complete its investigations by the end of this year, finish the trial process by 2008 and wrap up all appeals by 2010.

Mr. Amoussouga says a shortage of funds will delay these target dates. He says the tribunal has already streamlined operations and imposed a hiring freeze to cope with the shortfall.

The tribunal has often been criticized for being too slow. Since the first trial was held in 1997, 22 former government ministers, journalists, army officers and others have been tried and most of them convicted of genocide. Another 21 suspects are under indictment.