At present, Physics, Biology and Chemistry papers, have to be finished in one-and-a-half hours like any other paper, which students and schools felt was not enough.
CISCE chief executive and secretary Gerry Arathoon said time for other subjects as well as the duration for Class XII exams would, however, remain the same.
He also said the council would award provisional affiliation to schools that want to ugrade ICSE schools to ISC (Class XII) without having to receive a no-objection-certificates from the government.
Revision in syllabus would also take place in the future, he said but did not specify the changes.