Brazilian President Luiz Inacio Lula da Silva has concluded a five-nation visit to west Africa with a stop in Senegal, where he issued an apology for Brazil's role in the slave trade long ago.

President da Silva spoke about slavery Thursday at Senegal's Goree Island, a departure point for African slaves heading for a life of toil in the new world.

Brazil took in well over four million slaves from Africa - more than any other Western Hemisphere nation - and did not outlaw slavery until late in the 19th century.

Senegalese President Abdoulaye Wade and Mr. da Silva, who also held talks Thursday, pledged to strengthen their countries' trade and discussed cooperation in the areas of telecommunications, culture and sports.

The Brazilian leader's West African tour also took him to Ghana, Guinea-Bissau, Cameroon and Nigeria.