"We urge the Maoists to stop attacking unarmed civilians, including political activists, and stop extortion," the top leaders of seven parties said in a statement.
"We appeal to the rebels to create an atmosphere of confidence and demonstrate that they are sincere about talks with the political parties."
Nepal's parties have been protesting against the Feb. 1 sacking of the multi-party government by the king, who also suspended civil liberties and curbed media freedom.
Earlier this month, the elusive Maoist guerrilla chief Prachanda proposed talks with political parties to discuss the possibilities of common protests against the king to press him to roll back his seizure of power.
The rebels -- since launching their violent campaign to set up a single-party communist republic by toppling the monarchy -- have killed hundreds of civilians, including political workers, straining their ties with mainstream political groups.
In April, a landmine planted by the Maoists killed 38 civilians on a bus, but the rebels apologised saying the device was aimed at an army convoy.
The king has ignored international pressure, including from the United States, to restore democracy and analysts say he is far from cutting any deal with the parties or the Maoists.
Gyanendra said he seized power as squabbling parties had failed to control the Maoist rebellion which has left more than 12,500 people dead since 1996.
- Reuters - Thomson Reuters Foundation
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