"Yes to reforms," he said at a news conference in Sanaa, The Washington Post reported. "No to coups and seizing power through anarchy and killing. … You are calling for the regime to go -- then come and get rid of it through the ballot boxes, not through violence."
Opposition parties say they will not talk with a government that has attacked protesters with "bullets and sticks and thuggery."
Saleh, who is under pressure from the United States and other allies to curb bloodshed, said security forces would not fire at protesters, except in self-defense. On Sunday, he told supporters he condemned violence by pro-government gangs and they were not from his party.
At least 12 people have been reported killed nationwide, but relative calm prevailed in the capital for the past two days.
Several thousand people staged a sit-in in front of Sanaa University Monday, including legislators from opposition parties who may be shifting to demand regime change rather than reforms.