Katumbi, who was at one point viewed as the greatest political threat to former President Joseph Kabila, arrived by private jet after having recently received a new Congolese passport following several unsuccessful attempts to return.
"I have come back for peace, for the reconstruction of this country and above all to defend the rights of the people," said Katumbi, who arrived dressed in all white.
The 54-year-old businessman was unable to participate in the long delayed presidential election held in late December to replace Kabila, who had been in power for 18 years.
Katumbi was convicted in absentia in 2016 on real estate fraud charges and sentenced to 36 months in prison, a move his supporters said was aimed at derailing his presidential ambitions. He fled the country after accusing authorities of trying to poison him.
Last month, however, his conviction was overturned and he was issued a Congolese passport.
Observers say Katumbi still has political ambitions and is likely to be a player in the next round of elections in 2023.
Felix Tshisekedi, the son of the longtime opposition figure who died in 2017, was declared winner of the Dec. 30 presidential vote. One of his opponents Martin Fayulu maintained he was the rightful winner and accused Tshisekedi of making a deal with Kabila.
Katumbi, the former governor of Katanga province, is also the president and owner of TP Mazembe, a popular soccer team in Lubumbashi.
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