Donald Trump’s ambassador to Germany has suggested he will intervene in European politics to “empower conservatives”, in comments that have been criticised as going far beyond the traditional remit of a diplomat.

“There are a lot of conservatives throughout Europe who have contacted me to say they are feeling there is a resurgence going on,” ambassador Richard Grenell told the far-right publication Breitbart.

As Slovenia became the latest European democracy to elevate a politician espousing a populist form of conservatism, Mr Grenell said he wanted to “empower other conservatives throughout Europe”.

“I think there is a groundswell of conservative policies that are taking hold because of the failed policies of the left,” Mr Grenell said.

Chris Murphy, a Connecticut senator who sits on the Foreign Relations Committee, tweeted that he found Mr Grenell’s Breitbart interview “awful” to read.

“When I raised concerns to Grenell about politicising this post, he personally assured me that once he became Ambassador he would stay out of politics,” he said.

“Ambassadors aren’t supposed to ‘empower’ any political party overseas.”

An anti-establishment message intertwined with hostility to immigration helped propel Mr Trump to victory – themes that have reverberated through a string of European elections. Mr Grenell cited that precedent as helping to inform his mandate.

German election 2017 Show all 14 1 /14 German election 2017 German election 2017 German Chancellor Angela Merkel (R) poses for a selfie with a boy before addressing an election campaign rally of the Christian Democratic Union (CDU) in Kappeln Odd Andersen/AFP German election 2017 German Social Democrat (SPD) and chancellor candidate Martin Schulz speaks during an election campaign stop on September 20, 2017 in Gelsenkirchen. Schulz trails Chancellor and Christian Democrat (CDU) Angela Merkel by double digits Sascha Schuermann/Getty Images German election 2017 Sahra Wagenknecht, top candidate of the left-wing Die Linke party for upcoming general elections, gives a speech during a session at the Bundestag (lower house of parliament) in Berlin on September 5 John MacDougall/AFP German election 2017 Top candidate for the Greens for the 2017 German federal elections, Cem Ozdemir, speaks during an election campaign rally of the Alliance '90/Greens in Stuttgart, southern Germany on September 20, 2017, during the final days before Germans head to the polls Thomas Kienzle/AFP German election 2017 Leader of the Free Democrats (FDP) and main candidate in the upcoming parliamentary elections, Christian Lindner gives a speech during the party congress in Berlin on September 17 Odd Andersen/AFP German election 2017 Alice Weidel and Alexander Gauland, co-lead candidates of the right-wing, populist Alternative for Germany (AfD) political party, speaking to the media on Islam, immigration and crime next to an AfD poster that reads: 'Crime Through Immigration, The Refugee Wave Leaves Behind Clues!' on September 18, in Berlin Tobias Schwarz/AFP German election 2017 People listen to German Chancellor and Christian Democrat (CDU) Angela Merkel speak at an election campaign stop on September 19, 2017 in Schwerin Getty German election 2017 Refugees from Syria prior to the arrival of German Chancellor and Christian Democrat (CDU) Angela Merkel at an election campaign stop on September 19, 2017 in Schwerin Sean Gallup/Getty Images German election 2017 The audience cheers whilst listening to German Social Democrat (SPD) and chancellor candidate Martin Schulz speaking during an election campaign stop on September 14 in Munich Joerg Koch/Getty Images German election 2017 German Chancellor Angela Merkel holds up a tomato as she addresses an election campaign rally of the Christian Democratic Union (CDU) in Lingen on September 13 AFP/Getty Images German election 2017 Alexander Gauland, top candidate of Germany's anti-Islam, anti-immigration AfD (Alternative fuer Deutschland) party for upcoming general elections, walks past supporters as he attends an election campaign event in Nuremberg Daniel Karmann/AFP German election 2017 British politician and former UKIP leader Nigel Farage speaks at an event held by the German right-wing, populist Alternative for Germany (AfD) political party as AfD leading member Beatrix von Storch looks on on September 8, 2017 in Berlin Sean Gallup/Getty Images German election 2017 Martin Schulz (C), chancellor candidate of the German Social Democrats (SPD), looks on in a fest tent at the Gillamoos amusement fair on September 4, 2017 in Abensberg, Germany. Politicians, among them elections candidates, from Germany's major political parties are attending the fair today in what is an an annual tradition Johannes Simon/Getty Images German election 2017 An Alternative for Germany (AfD) campaign poster is vandalised in Berlin. Germans go to the polls on September 24th, with the AfD widely expected to garner enough votes to enter the federal parliament. Campaign poster reads: 'New Germans? we'll make them ourselves.' AFP

“I look across the landscape and we’ve got a lot of work to do, but I think the election of Donald Trump has empowered individuals and people to say that they can’t just allow the political class to determine before an election takes place, who’s going to win and who should run”, Mr Grenell said.

He offered praise for Austrian chancellor Sebastian Kurz, calling him a “rock star”. The young leader of the conservative Austrian People’s Party has formed a coalition with the far-right Freedom Party.

Austrian election results: Who is Sebastian Kurz?

The news organisation that ran the exclusive interview with Mr Grenell has itself helped to nourish the same political forces the ambassador said he would cultivate.