The government of Ivory Coast incumbent leader Laurent Gbagbo said on Saturday a threat of force by West African leaders calling for him to step down after last month's disputed election was "unjust".
Heads of state from regional bloc ECOWAS late on Friday added to world pressure on Gbagbo to cede power to rival presidential claimant Alassane Ouattara, saying he could face "legitimate force" if he refuses.
It was the first direct threat of foreign military intervention in the election standoff, which has killed nearly 200 people since the Nov. 28 vote and threatens to rekindle a civil war in the world's top cocoa grower.
The United States, which has imposed travel sanctions on Gbagbo and his inner circle, said late on Friday it supported ECOWAS's role in solving the crisis.
"We are surprised that there is such an escalation of sanctions and taking of positions against Ivory Coast over an election dispute," said Gbagbo's government spokesman Ahoua Don Mello in an interview with Radio France Internationale on Saturday. "That is very unjust."
The ECOWAS declaration said the bloc would send an envoy to Ivory Coast to deliver an ultimatum to Gbagbo. It did not specify when the envoy would be sent or who the envoy would be and officials could not immediately be reached for comment.
The United States, United Nations, European Union, African Union and ECOWAS have all recognised the provisional electoral commission results showing Ouattara as the winner.
But Gbagbo has shown no sign of caving in and insists he won the election after the Constitutional Court, which is headed by one of his allies, threw out hundreds of thousands of votes from pro-Ouattara constituencies.
The standoff turned violent last week after brief gun battles between government soldiers loyal to Gbagbo and rebels who now back Ouattara. The United Nations and human rights groups have said gunmen are now attacking pro-Ouattara neighbourhoods by night, kidnapping and killing people.
Deteriorating security in the former French colony led France this week to urge its 13,000 citizens there to leave.
The West African regional central bank last week cut Gbagbo off from the Ivorian accounts, deepening a cash crunch that could make it hard for him to continue paying the wages of soldiers who back him.
The move came on the heels of a decision by the World Bank to freeze some $800 million in committed financing.
Military support for Gbagbo is regarded as one of the main reasons he has been able to defy calls to step down.
Ivory Coast's $2.3 billion bond due in 2032 fell to a record low last week as investors worried that the country would not meet a $30 million bond payment on Dec. 31.
The turmoil in Ivory Coast has also thrust cocoa prices up to recent four-month highs, disrupting export registrations and raising fears that fighting could block transport and shipping.