The 30-year-old is the second major signing for Petrolul during the winter break after Romania's joint top international goal-scorer Adrian Mutu also returned to his homeland after leaving French Ligue 1 club Ajaccio.
"Today is an important day in my career and I'm very happy that I was given the opportunity to come to this club, a true symbol of the Romanian football," Zicu told a news conference.
The much-travelled Zicu, who scored 21 goals in 72 internationals, joined Inter Milan from Dinamo Bucharest in 2004 after winning two league titles and one Romanian Cup but was immediately sent on loan to Parma.
He also played for Romanian clubs Poiana Campina, Farul Constanta, Rapid Bucharest and Politehnica Timisoara, Bulgaria's CSKA Sofia and South Korea's Pohang Steelers.
His move to Petrolul reunites Zicu with former Romania team mate Cosmin Contra, who was appointed as coach in 2012.
Petrolul, knocked out of the Europa League in the playoffs in August, are second in the championship on 40 points from 19 matches, two behind leaders FC Astra.
- Sports & Recreation
- Adrian Mutu