Nour said: "Our movement was in a great struggle... but now we must speed national reconciliation and bring peace to our country."
Sunday's signing ceremony between Nour and Idriss Deby, Chad's president, was held in Tripoli, Libya's capital, and hosted by Moammar Gaddafi, the Libyan president.
Gaddafi said: "I hope that the raging fire in the African Horn will be extinguished. Goodwill must be stronger than the will to destroy."
Chad's government has said the two sides agreed to release each other's prisoners and grant an amnesty to fighters from both sides.
It was also agreed that Nour's forces would be stationed at a location agreed by both sides until they could be integrated into the national army.
"For us this changes nothing. We're not interested in any mediation by Gaddafi, or by France, or by anyone"
National Rally for Democracy spokesman
The agreement is to be implemented over a three month period and other rebel groups have been given a month to join the accord.
Deby said: "This is a great day for us. Today we made a step forward on the path towards peace in Chad."
Deby and Nour are expected to return to N'Djamena, Chad's capital, together.
A large number of rebel groups are active in Chad, including Nour's United Front for Democratic Change faction.
Makaila Nguebla, a spokesman for the National Rally for Democracy said on Sunday that fighting would continue.
"For us this changes nothing. We're not interested in any mediation by Gaddafi, or by France, or by anyone. We are going to continue to fight this regime," he said.
Nour, whose forces raided N'Djamena in April, called on the other rebel groups to sign the peace agreement and join the Chadian government.
He said: "We thank God for enabling us to reach this agreement... and we urge our colleagues to join it."
Deby has accused Sudan of funding and arming the rebel groups as well as the Arab Janjawid fighters who conduct raids across the border.
|President Deby has accused Sudan of funding |
rebel groups in Chad [AP]
Sudan has denied the accusations and has accused Chad of supporting rebel groups active in Sudan.
Many analysts have warned the violence in eastern Chad and in Sudan's Darfur area could extend to engulf the entire region.
Gaddafi has for a while been pressing Chad and Sudan to settle their differences as part of international efforts to bring peace to Sudan's western region of Darfur.
Since early November, some 300 people in eastern Chad have been killed in attacks on more than 70 villages, according to the United Nations.