South Sudanese rebel leader warned President Salva Kiir on Wednesday that the country’s civil war will continue and the people will "rise up and overthrow his regime" if he stays in power.
Riek Machar's statement also warned of escalated violence on the part of rebels. The speech was delivered in Nairobi after South Sudan's parliament speaker formally extended President Kiir's term for three more years, a move approved by lawmakers in a March vote.
The war torn African nation of South Sudan has been plunged in brutal turmoil in December 2013. The rebels say that the country’s parliament doesn’t have the legal jurisdiction to elongate Kiir’s stay in the office.
"Should President Kiir remain adamant and refuse to hand over power to the people, then the citizens have every right to rise up and overthrow his regime," Machar said in the statement made on a visit to Nairobi.
He said Kiir's term ended at midnight on July 8.
South Sudan will mark its fourth anniversary of independence from Khartoum on Thursday as one of the world’s newest nations. The conflict in the country began when Kiir fired Machar as his deputy after suspecting an attempted coup in 2013.
The conflict has sparked a series of retaliatory killings. All parties are accused of committing atrocities including the South Sudanese army.
Amid on again/off again peace talks in Ethiopia, South Sudan has failed to end fighting which has killed thousands of people and driven more than 2.2 million from their homes, many of them fleeing to neighbouring states, including Kenya.
"The people of South Sudan did not deserve to go back to war, but this was caused by the actions of President Salva Kiir, who we ask to resign today," Machar said.
"We don't feel like we have a peace partner with Salva Kiir."
A UN report last month described horrific violence in the latest fighting, with witnesses saying troops gang-raped girls and torched them alive in their homes. In addition, large numbers of child soldier have been recruited to fight in the war.
Machar welcomed into his ranks a rogue ex-government general, Johnson Olony, last month. Olony has been accused of forcibly recruiting hundreds of child soldiers.