According to a Court order issued on Thursday, the prosecution must file its submissions by September 5, while the defence and representatives of the victims have until September 10 to file any observations.
Kenyatta, who was elected president in March 2013, is accused of crimes against humanity committed during post-electoral violence in his country in 2007-2008.
His trial was originally due to start on February 5, but was postponed after ICC Prosecutor Fatou Bensouda on December 19 asked for an indefinite delay.
She asked for more time to boost her evidence after the withdrawal of two key witnesses. One said he was no longer willing to testify in the case, while the other said he had given false evidence.
In a March 31 decision, the Court set the start of trial for October 7. The judges now want to ensure that the Prosecutor is finally ready, so that they can issue practical instructions to the parties for smooth organization of the hearings.
In this judicial saga, which may yet turn up more surprises, the prosecution is facing not only the withdrawal of witnesses but also strong pressure from some African leaders.
Since Kenyatta and his Deputy President William Ruto were elected -- despite the ICC accusations against them --, the African Union has mobilized, claiming that serving leaders of their rank should not be prosecuted by the ICC.
In Ruto’s trial, which has been ongoing since September 2012, the judges agreed to a softening of rules so that he may be absent from certain hearings to carry out his national duties.
It remains to be seen whether Kenyan head of state Uhuru Kenyatta will also be able to work with this arrangement.