Jo Swinson: Boris Johnson is 'not fit to be prime minister'

Liberal Democrat leader Jo Swinson has reacted to the the Supreme Court's decision that the PM acted unlawfully in proroguing parliament. .

She said Boris Johnson had tried to "silence Parliament, tried to silence the voices of the people because he does not want to be held to account".

Britain's highest court's ruling is a heavy blow to the prime minister and opposition politicians have accused him of lying to the Queen . Some have called for his resignation.