Germany's foreign minister said on Sunday that a speech by Syrian President Bashar al-Assad offered "no new insights" and urged him to make way for a new start in the conflict-riven country.

"Unfortunately the Assad speech contains no new insights," Guido Westerwelle said in a written statement.

"Instead of martial tones again, he should finally free the way up for a transition government and a political new start in Syria," he added.

And he called for Assad "not only to vaguely declare the readiness for a ceasefire, but to finally stop the violence of his troops".

Assad offered a road map to end Syria's civil war in a rare speech Sunday in which he branded the opposition "slaves" of the West and told foreign powers to end their support for rebels.