Australian Government insiders have hit back at Britain over "sledging" by Liz Truss’s allies ahead of trade talks this week. The Telegraph revealed on Tuesday that sources close to the International Trade Secretary were briefing that Dan Tehan, the Australian trade minister, was "inexperienced" in comparison. Allies of Ms Truss complained of "glacially slow" progress over a UK-Australian trade agreement, and warned that Mr Tehan "needs to show that he can play at this level" when the pair meet for negotiations on Thursday. They also claimed that the British cabinet minister was plotting to sit Mr Tehan "in the Locarno Room [in the Foreign Office] in an uncomfortable chair, so he has to deal with her directly for nine hours". An Australian minister told this newspaper that the remarks were "full of hubris" and hit back that Mr Tehan is "from the land" and "has the stamina" to see off Ms Truss’s tactics. Unimpressed, the frontbencher commented ironically: "I love it when Brits underestimate us." The minister, speaking on condition of anonymity, continued: "Sledging is a fine art, which we have mastered on the pitch. This is just the Brits gobbing off." Australian officials also weighed in to counter the UK Government briefing. An official at the country’s Department of Foreign Affairs and Trade said: "If this was briefed by a member of Truss’s staff, that is very disrespectful." The official told the Sydney Morning Herald: "It’s also a very bad tactic. It won’t work." In response to the claim that Mr Tehan was "inexperienced" in trade talks, it was pointed out that while Mr Tehan only took on the post of trade minister in December, he first joined DFAT in 1995. He served as a diplomat between 1999 and 2001, and between 2002 and 2005 worked as a trade adviser to the minister, helping to negotiate Australia’s free trade deal with the US administration under George W Bush. Ms Truss is said to have texted Mr Tehan on Tuesday night to say she was looking forward to seeing him and hoped for a productive two-day dialogue in London. The UK High Commissioner Vicki Treadall faced questions over the UK briefing. She defended the sources close to Ms Truss, insisting that Australia is one of "our closest friends and allies", but that "this is a trade negotiation so there will be tactics on both sides". Some British politicians also took a dim view of the briefing. Alistair Carmichael, Lib Dem MP and home affairs spokesman, branded it "embarrassing" and tweeted: "It's also a reminder that the Government has chosen to turn trade negotiations with a supposed ally into another avenue for domestic politics, on the bet that no one will notice the long-term negative side effects."