Boris Johnson needs to pick up the phone to European leaders if he is serious about salvaging a free trade deal with Brussels, EU diplomatic sources have warned. Trade negotiations could drag into December or fail completely, they said unless Mr Johnson stopped being so “detached” and “absent” from Brexit. “Is he even interested? What does it say to the 27 leaders when an issue as important as this is only dealt with by David Frost [the UK’s chief negotiator]?,” said a senior EU diplomat. “It’s about time people higher up in the hierarchy start involving themselves if they want to achieve something.” The UK and EU have agreed to intensify talks in an effort to agree a trade deal by Mr Johnson’s deadline of the October 15 EU summit, which is in nine days’ time. Leaked documents for EU Brexit meetings on Wednesday said that there was “no significant progress” towards a deal in the last round of talks and predicted the European Commission would “shortly” bring forward no deal legislation. EU governments have become so pessimistic, the Telegraph understands, that at least one member state has already begun war-gaming post no deal Brexit negotiations. European capitals said Mr Johnson “didn’t have much to say on substance” when he held urgent Brexit talks with Ursula von der Leyen, the president of the European Commission, on Saturday. The diplomat contrasted Mr Johnson’s style unfavourably with former prime minister Theresa May who was “always” on the phone to fellow leaders such as Angela Merkel and Emmanuel Macron. “The chances of there being a deal are becoming less and less by the day, that’s clear,” the senior diplomat said, “But one reason why our leaders can’t do much is because Boris Johnson hasn’t been engaging.” UK sources said that Lord Frost handled negotiations on the basis of the EU’s own rule that Michel Barnier negotiated on behalf of the whole EU. It was up to the bloc to ensure UK positions were communicated to its capitals, they said. The EU has always been highly sensitive to any suggestion that the UK could be going over Mr Barnier’s head but sources said Mr Johnson could open channels of communication without undermining the French official.