CAIRO (AP) — Egyptian President Mohammed Morsi offered nothing concrete to defuse the country’s worst political crisis in nearly two years in a nationally televised speech late Thursday, refusing to rescind a disputed constitution drafted by his allies or his decrees giving him near absolute powers.

A night after thousands of his supporters and opponents fought pitched battles outside his Cairo palace that left at least six dead and nearly 700 injured, he angrily accused some of the opposition protesters of serving remnants of the old regime. He vowed never to tolerate anyone working for the overthrow of his ‘‘legitimate’’ government.