Syrian President Bashar al-Assad has accused Britain of having a "naive, confused and unrealistic" approach to his country's bloody civil war.
Speaking to The Sunday Times correspondent Hala Jaber, President Assad said Britain had a poor history of negotiating peace and accused the British government of "militarising" the conflict for its own ends.
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Among those expected to attend the ceremony will be former US President Bill Clinton and ex-Northern Ireland first minister Peter Robinson.
Five people have been killed and 40 injured after a car and knife attack in London on Wednesday.
A wet, wintry night in places with rain and hill snow slow to move away from southern Scotland and northern England.