Ivorian opposition leader and former Prime Minister Alassane Ouattara has returned to Ivory Coast after more than three years in exile in Paris.
Alassane Ouattara was greeted by supporters at Abidjan airport
On his arrival, a few days after he announced his intention to stand in presidential elections to be held later this year, he called for unity.
Mr Ouattara was controversially barred from standing in 2000 elections because of a dispute over his nationality.
He is seen as the main challenger to current President Laurent Gbagbo.
Since an abortive coup in 2002, Ivory Coast has been divided between the government-controlled south and rebel-controlled north.
A UN-backed peace plan aims to reunite the country by the end of October through presidential elections.
IVORY COAST CONFLICT
Sept 2002: Dissident soldiers fail to overthrow President Gbagbo, but rebels seize north of country
May 2003: Armed forces sign ceasefire with rebel groups
Nov 2004: Ivorian air force attacks rebels; French forces destroy parts of Ivorian air force after nine of their soldiers killed. Violent anti-French protests prompt thousands of Westerners to leave
Oct 2005:UN extends President Gbagbo's mandate for 12 months and postpones elections
Mr Ouattara, who was prime minister from 1990 to 1993 under former President Felix Houphouet-Boigny, briefly came back to Ivory Coast in December for his mother's funeral.
On his latest return, he was greeted by several dozen supporters and the UN peacekeepers assigned to protect him.
"It is with much love that I return to the soil of my country to take part in the political process," he told reporters at Abidjan airport.
"I launch an appeal for union, for calm... so we can find together truly democracy in peace."
Saying the country's greatest difficulties lay ahead, he urged young Ivorians to concentrate on improving its economic and social situation.
Mr Ouattara, head of the Rally of the Republicans (RDR) party, has been accused of supporting rebels who control the north of the country, an allegation he denies.