KHARTOUM Aug 21 (Reuters) - Sudanese President Omar Hassan al-Bashir on Thursday proposed a two-month ceasefire with rebels fighting to overthrow his government and set a date for a new meeting in a national reconciliation process that collapsed in January.

Bashir also repeated his offer of amnesty for rebels who agreed to put down their arms and join the national dialogue between the government and opposition parties.

The renewed dialogue will take place on Oct. 10, he said at a meeting to plan the future of the process with the handful of parties that will participate.

Eighteen of the 21 opposition parties that had initially agreed to participate in the dialogue at its inception in early 2014 pulled out this January, leaving the future of the reconciliation process in question.

"We announce our readiness for a ceasefire for the two months until the dialogue...to ensure the success of dialogue," said Bashir, who was reelected with 94 percent of the vote this April in an election largely boycotted by the opposition.

The armed groups could not immediately be reached for comment on the ceasefire or amnesty but the rebels have rejected previous amnesty offers.

Sudan's government has faced a rebellion in its Darfur region since 2003 and a separate but linked insurgency in Blue Nile and South Kordofan since the secession of South Sudan in 2011.

The government has rebuffed opposition and rebel demands to link political negotiations with peace talks. (Reporting by Khalid Abdelaziz, Writing by Shadi Bushra, Editing by Angus MacSwan)