US President Barack Obama has discussed "possible responses by the international community" to Syria with French President Francois Hollande.
The White House said they agreed to "continue to consult closely" after accusing the Assad regime of using chemical weapons against its own people last week.
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Government ministers from the UK, France and China attended the event.
Tonight investigates the increasingly sophisticated methods criminals are using to target the elderly and defraud them of their savings.
If you've been anywhere near Trafalgar Square today you'll notice something different.