The All Progress Congress (APC) says the Peoples Democratic Party (PDP) cannot prevent its candidates being put through the corruption and integrity test.
The APC stated this in a statement by its publicity secretary, Yekini Nabena, on Thursday.
The party was reacting to a statement by spokesperson of the PDP, Kola Ologbondiyan, in which he accused the APC-led administration of "deliberate efforts to impugn on the character" of the PDP presidential candidate, Atiku Abubakar.
"The PDP cannot be simplistic and attempt to wish away the issue of the integrity of candidates seeking elections into positions at all levels, particularly as 2019 approaches," Mr Nabena said.
"We reiterate our position that the Nigerian electorate must have that opportunity to choose from candidates that can pass the integrity and anti-corruption test.
"The character of office holders we elect into public offices is important as our very progress and development as a country depends on it.
"When the choice is to be made, the electorate have the option of a proven and decent presidential candidate who is putting the people first and on the other hand a racketeer who will readily mortgage the country's commonwealth to personal coffers and cronies."
APC said the opinion of the PDP that its comment was a deliberate attack on the character of Mr Abubakar, is laughable.
It alleged that the spokesperson of PDP once did a report which indicted Mr Abubakar.
"Coming from its spokesperson is ironic and laughable, given the fact that Mr. Kola Ologbondiyan as an editor with one of the national newspapers in fact unearthed the Special Audit/Forensic Investigation of Petroleum Technology Development Fund (PTDF) which indicted Alh. Atiku Abubakar, then Vice President for the mismanagement of the Fund.
"The PDP spokesperson in his published report disclosed that from 1999 to 2006, Atiku's approval for the release of $20m from the treasury and subsequent placement in Trans International Bank without appropriation and approval by the Federal Executive Council (FEC) was illegal and amounted to abuse of office."
The party said its claims are not false, insisting that Mr Abubakar has several corruption indictments he must come to terms with.
"There are no lies here. Alh. Atiku Abubakar grapples with several other corruption indictments. This is a fact and reality he needs to deal with and come clean about."