Bemba “could fall within the ambit of article 10 of the electoral law” finding those who have convictions for corruption “ineligible,” Alain Atundu, spokesman for the Presidential Majority, told AFP.
Atundu said he hoped that Bemba would “solemnly” commit to not running “if he is found to be ineligible under the electoral law”.
The International Criminal Court (ICC) last month overturned on appeal an initial 18-year term for war crimes and crimes against humanity for Bemba, a former vice president, finding he could not be held responsible for crimes committed by his troops.
But in March 2017 he was also convicted for bribing witnesses.
Earlier this month the ICC urged that he be given a five-year term on that count but no date has been fixed for a verdict.
This week Bemba said he would arrive in the capital Kinshasa on August 1 after his party, the Movement for the Liberation of the Congo (MLC), announced he was filing his candidacy for the presidential election.
Bemba, a senator, is currently in Belgium and must give the ICC details of his whereabouts when required.
The government recently accorded him a diplomatic passport.
Kabila, who has ruled since 2001, has refused to spell out whether he will seek a new term in office in the crucial December 23 election.
Dozens of people have been killed in protests since late 2016, when Kabila was scheduled to stand down at the end of his second elected term, technically the last permitted under the constitution.
August 8 is the deadline for candidates to submit applications.
The DRC, a mineral rich country but one of Africa’s most volatile countries, has never known a peaceful transition of power since it gained independence from Belgium in 1960, and some experts fear that the December election may trigger a bloody conflict.