South Sudan's parliament has voted to extend its own term and that of President Salva Kiir by three years starting from July.
Last month, South Sudan called off the elections due in June and its cabinet asked the parliament to extend Kiir's term.
The government had said it was necessary for stability amid an ongoing rebellion led by a former deputy president, Riek Machar.
The measure, passed by more than two-thirds of the MPs on Tuesday, also extends the tenure of the legislature, MP Thomas Kundu, who heads the parliament's information committee, told the Associated Press.
"We believe these three years will give a chance for peace so that all of us prepare to conduct a census and after which we can conduct free and fair elections,'' Kundu said.
However, the opposition condemned the measure, saying it was meant to keep Kiir firmly in power.
"It means the government wants to cling onto power,'' said Onyoti Adigo, a member of the opposition in parliament who voted against the measure.
"The people were not consulted. That is why we are opposed to it.''
Thousands of people have been killed and more than a million have fled their homes since fighting between supporters of Kiir and Machar erupted in the world's newest nation in December 2013.
Kiir, a member of the dominant Dinka ethnic group, tried to put down rebels led by Machar, who is of Nuer ethnicity.
Peace talks between Kiir and Machar have repeatedly failed. The fighting has often been along ethnic lines.