LONDON (Reuters) -Britain will not hesitate to toughen sanctions on Moscow and will look to contribute to any NATO deployment if Russia invaded Ukraine, Prime Minister Boris Johnson said on Tuesday. NATO said on Monday it was putting forces on standby and reinforcing eastern Europe with more ships and fighter jets, in what Russia denounced as Western “hysteria” in response to its build-up of troops on the Ukrainian border. “We in the UK will not hesitate to toughen our national sanctions against Russia in response to whatever President (Vladimir) Putin may do and the House (of Commons) will so…