Nuwan Bopage said that the bench comprising of three army officers postponed the hearing on Wednesday, Mar 17.
The bench would seek President Mahinda Rajapaksa opinion on whether both the charges against Fonseks should be heard.
The officers have not revealed the reason for the postponment.
On Tuesday, Mar 16, Fonseka appeared before the court martial in connection with the charges that he had made arrangement for his Presidential campaign, even when he was still in office.
He was scheduled to answer before the court on Wednesday, Mar 17, whether he had violated the procedure in purchasing military ware.
The defeated Sri Lankan Presidential candidate was arrested on Feb 8 for allegedly plotting military coup against President Mahinda Rajapaksa.