(CNN) -- Lawyers for a leading Kenyan presidential contender want the International Criminal Court to take a step backward in his trial for alleged human rights violations, saying a crucial prosecution witness lied.
Uhuru Kenyatta is the current deputy prime minister and a frontrunner in the presidential election next month.
His defense is seeking a review of the case, saying doing so will avoid "a serious miscarriage" of justice.
In a document released Wednesday, Kenyatta's lawyers said a witness identified as "OTP-4" lied about attending a meeting that the candidate was allegedly holding with the Mungiki, an outlawed sect of fighters.
Mungiki fighters are alleged to have conducted bloody attacks during the aftermath of the 2007 disputed elections.
The ICC has said Kenyatta and a co-perpetrator directed the outlawed sect to attack opposition members and rival tribes during the postelection unrest.
Following the revelation about "OTP-4," the ICC dropped the witness from the proceedings, according to the defense. Prosecutor's documents now don't show any evidence that Kenyatta attended the meeting, the defense said.
"In the circumstances, a key fact underlying the confirmed charges has been established to be based upon a lie," the lawyers said.
Despite the claims, the ICC said the trial will continue as planned April 10 and 11.
"The channel to respond to all submissions presented to the Chamber by any party to proceedings before the court is through a filing to the judges and not through the media," the court said in a statement.
Kenyatta and his alleged co-perpetrator Francis Muthaura are among four people accused in the postelection violence, which left more than 1,000 people dead and hundreds of thousands displaced.
The court's pretrial chamber confirmed charges against the four last year.
Kenya had earlier challenged the jurisdiction of the International Criminal Court, saying its own authorities would investigate and prosecute the cases.
Kenyatta hails from an influential political family in the east African nation. He is the son of Kenya's founding father, Jomo Kenyatta.