NBC producer Kristen Welker has reported that the US Secret Service has revoked the top secret security clearances of all 11 agents and officers.
"Pending investigation, their top secret clearance has been revoked," George Ogilvie, a Secret Service spokesman, said.
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Sergei and Yulia Skripal remain unconscious and in critical conditions following the March 4 attack in Salisbury.
Sir Vince Cable said it was clear that Britain's EU partners would welcome a change of heart on Brexit 'with open arms'.
Visitors to Salisbury city centre are down 90% in the wake of the nerve agent attack on former Russian spy Sergei Skripal and his daughter.