Libya ? Two major Darfur rebel groups said Friday they plan to boycott upcoming peace talks, a major blow to negotiations the U.N. hoped could reach a new agreement for the Sudanese region torn by years of fighting.

The absence of the Justice and Equality Movement and SLA-Unity groups means at most only a few minor rebel factions, if any, will attend the conference beginning today in Sirte, Libya. The groups jointly decided upon the boycott because the mediators’ decision to invite factions they claim have little popular support, said Mohammed Bahr Hamdeen, a senior JEM leader.

“The mediation has fallen in the trap prepared by the government by making the negotiations an arena for every Jack, Tom and Harry,” Hamdeen said.

The announcement was a serious blow to potential progress at the peace talks, which are being hosted by Libyan leader Moammar Gadhafi and mediated by the United Nations and the African Union.