Kazakhstan's parliament has voted in favour of holding a referendum on extending the term of President Nursultan Nazarbayev until 2020.
Mr Nazarbayev, who has led Kazakhstan for 20 years, said last week he did not support plans for the referendum.
Such a vote would bypass the need for the next two presidential elections - the first scheduled for 2012.
Parliament says Mr Nazarbayev should stay in power to ensure the country's "stable development" and prosperity.
The lower and upper houses of parliament voted unanimously to change the constitution to permit the referendum.
The vote came after a petition backing the referendum was signed by five million Kazakhs - about a third of the population.
Poor human rights
President Nazarbayev has led Kazakhstan since its independence from the Soviet Union in 1991.
Last week, the US called the referendum idea a "setback for democracy".
The US has fostered close ties with the mineral-rich country, despite the government's record on human rights, the stifling of opposition and the concentration of power in the hands of the president and his family.
Kazakhstan has never held an election deemed free and fair by international observers.
Parliament, made up entirely of members of the president's party, has already changed the constitution to allow Mr Nazarbayev to run for re-election as many times as he wants.