LONDON, Nov 7 (Reuters) - Significant differences remain in talks over a trade deal between Britain and the European Union, Boris Johnson’s office said after a call between the British prime minister and European Commission President Ursula von der Leyen. “The prime minister set out that, while some progress had been made in recent discussions, significant differences remain in a number of areas, including the so-called level playing field and fish,” a spokesman for Johnson’s office said. “The prime minister and president agreed that their negotiating teams would continue talks in London next week, beginning on Monday, in order to redouble efforts to reach a deal.” (Reporting by Michael Holden; editing by Jason Neely)