Speaking to jubilant supporters in front of his campaign headquarters after the election, Christofias pledged that he will work with all Cypriots to reunite the divided island.
"Tomorrow a new day will dawn, we have many difficulties ahead," he said. "We will join forces as of tomorrow, we will work together to reunite our country."
"I have often said that today our ideology is one: Cyprus and its salvation, this is the vision we are going to work for," he added.
Christofias thanked his rival Kasoulides, the outgoing President Papadopoulos and particular the younger generation during his speech.
Cyprus has remained divided since 1974 when Turkey militarily intervened and occupied the north of the island following a coup by a group of Greek officers who pushed for a union with Greece.
In 1983, the Turkish Cypriot authorities declared a breakaway territory and set up the Turkish Republic of Northern Cyprus, which is recognized only by Turkey.
In a referendum held in April 2004, Greek Cypriot under the leadership of Papadopoulos rejected the Annan Plan for fear that it would be in Turkey's favor, while Turkish Cypriot approved it.
After the presidential election, fresh efforts to revive the deadlocked reunification process are expected by both Greek Cypriot and Turkish Cypriot communities.
(Xinhua News Agency February 25, 2008)