Nigel Farage is to host a daily radio show of political debate.
The former Ukip leader was previously tipped by US president-elect Donald Trump as a potential ambassador to Washington and on Tuesday said he would "rather fancy" taking Sir Ivan Rogers' job as UK permanent representative to the EU - a post now filled by Sir Tim Barrow.
His new job will instead see him present an hour-long week-night phone-in on LBC radio.
He said the Nigel Farage Show would be "full of opinions, callers and reaction, as well as my nightly final thought on the events of the day".
But Liberal Democrats questioned whether the job - presented largely from LBC's studios in London - was compatible with his duties as a member of the European Parliament.
"Shouldn't he be, you know, turning up to his office in the European Parliament?" said a Lib Dem spokesman. "If not, maybe he could donate his MEP salary to the NHS?"
Mr Farage has previous radio experience hosting phone-in programmes and standing in for other presenters on LBC, and has this week been hosting a late-night show on the station.
He said: "If 2016 was exciting, then this year could be tumultuous with President Trump, Article 50, elections all over Europe and maybe a eurozone crash. I can't wait to start my daily show on LBC and I invite listeners to agree with me or challenge me and together we can lead Britain's conversation."
:: The Nigel Farage Show will be on LBC radio at 7pm Monday-Thursday from January 9.