The UN Security Council has imposed an arms embargo on the Ivory Coast and vowed to punish government and rebel leaders with more sanctions next month.
The UN is hoping to force both warring sides to return to the terms of a 2003 peace agreement.
Hopes for a peaceful end to the stalemate between rebels and President Laurent Gbagbo crumbled this month with an army assault on the rebel-held north.
Concern war in Ivory Coast could suck in west African neighbours has prompted talks among international diplomats and African leaders, desperate to stop a country once feted as a model of post-independence prosperity sliding into anarchy.
The 15-nation council unanimously adopted a sanctions resolution drafted by France, the former colonial power, after the government launched bombing raids on the rebel-held north a little over a week ago, shattering an 18-month truce and killing nine French peacekeepers and a US civilian.
South African President Thabo Mbeki said in Brussels he would meet rebel leader Mr Guillaume Soro later this week. Officials have said he might also host a summit in the next few weeks bringing all sides together.
Mr Soro said that while he was open to peace initiatives he had not been informed of the South African plans.
An army offensive against the north came to a halt more than a week ago when French troops crippled Ivory Coast's small air force in retaliation for the killing of nine French peacekeepers in a bombing raid on the rebel-held town of Bouake.