LONDON (Reuters) - Britain’s Brexit negotiator David Frost said he would do his utmost to see whether the conditions for a trade deal exist and, although late, he would work until it becomes clear that there is not. He said any deal must respect UK sovereignty. “We look to reach an agreement on this basis, allowing the new beginning to our relationship with the EU which, for our part, we have always wanted,” he said on Twitter. “We will continue to work hard to get it – because an agreement on any other basis is not possible.”