"I will seek authorisation for the use of force from the American people's representatives in Congress," President Obama said.
He said Congressional leaders agreed to "schedule a debate and then a vote as soon as Congress comes back in session."
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Ex-Dragon's Den star Doug Richard has pleaded not guilty to a string of child sex charges after appearing before the Old Bailey.
The independent child sexual abuse inquiry has named the first institutions facing investigation - including local councils and the Church.
The Queen has paid tribute to both her husband and son in her opening speech at this year's Commonwealth summit.