The Turkish government is planning a referendum next spring on amending the constitution to bolster the powers of the president.
Deputy Prime Minister Nurettin Canikli told Turkish television on December 9 that the government would send its plan to parliament later the same day.
He said the 316 lawmakers of the ruling AK Party and 39 from the Nationalist Movement Party (NHP) would be enough to secure a two-thirds majority in the 550-seat legislature.
Canikli did not say exactly what the proposed amendments would entail, but he said the government wants the process completed before the country holds presidential and parliamentary elections in 2019.
Also on December 9, Turkish prosecutors ordered the arrests of 87 people connected to Istanbul University as part of the ongoing crackdown against supporters of self-exiled cleric Fethullah Gulen.
President Recep Tayyip Erdogan's government blames Gulen for a failed coup attempt in July that left some 240 people dead. Gulen, who lives in the United States, denies all involvement.
Ankara has jailed about 36,000 people and removed or suspended another 100,000 from government posts since the crackdown began.