Addressing the nation President Assad said Syria "will not have a dialogue with a puppet made by the West".
The remarks were his first in public since a Russian television interview in November when he pledged to stay in Syria and fight to the death if necessary.
A 21-month uprising against Assad has become a civil war that the UN says has killed 60,000 people.
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Nearly 38,000 runners will hope to complete Sunday's London Marathon making it the biggest event in its 35-year history.
Rain across central Britain with longer, intense downpours with thunder in places this evening. A lucky few will stay sunny and dry.
Planning on going to the London Marathon tomorrow? Read our handy guide first!