CHISINAU, September 9 (RIA Novosti) - Moldovan Prime Minister Zinaida Greceanii has followed the president's example and announced her resignation, the government's press service said on Wednesday.

Acting president Vladimir Voronin formally announced his resignation last Wednesday to become a member of parliament, after strongly criticizing the incoming leadership. His and Greceanii's departure means the Communist Party is now an opposition movement and refusing any compromise with the parliamentary majority.

"I am doing this because I cannot combine the positions of prime minister and a member of parliament," Greceanii told a Cabinet session.

The communist faction has 48 seats in the 101-seat parliament following the July 29 parliamentary election re-run, down from the 60 seats secured in the April election, which triggered violent protests in the capital, Chisinau. The opposition twice blocked the election of the presidential candidate proposed by Voronin leading to the July 29 polls.

Under the country's constitution, newly elected parliamentary speaker Mihai Ghimpu, who had the backing of all 53 members of the Moldovan alliance For European Integration's, will become acting president. Ghimpu, who leads the Liberal Party, has openly supported unification with Romania.

The legislature must elect a new president, but the ruling majority currently lacks eight votes. If no president is elected, the legislature must be dissolved and a new parliamentary election called, according to the constitution. However, parliamentary elections may not be held more than twice a year, meaning no further elections can be held in 2009.