Syrian president Bashar Assad has denied reports that his government is targeting hospitals and civilian infrastructure.

Syrian opposition activists and international relief agencies have said Syrian and Russian war planes have been hitting hospitals and infrastructure in the northern city of Aleppo, which has been the epicentre of the Syrian civil war in recent months.

But Assad told Denmark's TV2 station that "to say this is our aim as a government, (that) we give the orders to destroy hospitals or schools or to kill civilians, this is against our interest".

Still, Assad said mistakes are sometimes committed by individuals in any war. Excerpts from the interview were released by Assad's office on Thursday.

Assad said that had his government been "committing all these atrocities", he could not have remained president.