Tribal and political leaders in eastern Libya declared the?oil rich?Cyrenaica an autonomous region?in the city of Benghazi on Tuesday.

Cyrenaica, known as Barca in Arabic, stretches from the central coastal city of Sirte, the birthplace of Libya's former leader Muammar Gaddafi, to the Egyptian border.

The leaders made the announcement at a ceremony attended by 3000 delegates.

They also appointed a council to manage the?regional affairs and elected Ahmed Zubair al-Senussi as chairman of the council.

Cyrenaica, known as Barca in Arabic, stretches from the central coastal city of Sirte, where the former leader Muammar Gaddafi was born, to the Egyptian border.

The tribal leaders plan to name Benghazi, the cradle of the protests leading to Gaddafi's fall, as the capital of the autonomous region.

According to their plan, the region will have its own legislatures, courts and police force, while the power of foreign policy making will be left to the central government in Tripoli.

The tribal leaders made the?declaration despite the interim central rulers' strong?opposition and their promise to decentralize the government across the country.

According to local TV report, head of Libya's ruling National Transitional Council (NTC) Mustafa Abdul Jalil slammed the council's establishment as "the beginning of a plot against Libya."

He also denounced Arab countries?for supporting and financing the "sedition" in eastern Libya.

Meanwhile, hundreds of protesters have reportedly taken to the streets in Benghazi and Tripoli, showing their support for the NTC .

Political changes in Cyrenaica can immensely impact the NTC's rule as the eastern region has most of Libya's oil wealth and Benghazi is home to the country's biggest state oil company.

Federalism, which the tribal leaders refer their political demand to be, was the way Libya was governed in the mid-20th century. Cyrenaica was one of the three regions where power was devolved, the other two being Fezzan and Tripolitania.

However, Libya's administration was drastically centralized under Gaddafi, who came to power through a military coup in 1969. Since the end of Gaddafi's 42-year rule, some regional leaders have been calling for a return to federalism.

The NTC has earlier voiced their support for a decentralized political system, but not federalism.