Disgraced columnist Johann Hari is set to return to his job at the Independent newspaper in 'four to five weeks', the Leveson inquiry into press standards has heard.

Chris Blackhurst, editor of the Independent, told the hearing on Tuesday that Hari "genuinely believed that he was doing nothing wrong" and after undergoing re-training was fit to again write for the paper as a columnist.

Hari, who has also blogged for the Huffington Post, on a voluntary basis, was accused as early as 2003 by Private Eye for publishing plagiarised articles, and in June last year the criticism became widespread after investigative work by the Deterritorial Support Grouppppp and journalist Brian Whelan, among others, were picked up by the Guardian and other newspapers.

At first Hari denied the accusations, but did admit that he had quoted people he interviewed "as they expressed [their thoughts] in writing, rather than how they expressed it in speech".

But the controversy persisted as other publications and bloggers compared Hari's work with other published articles, and appeared to find several cases of plagiarism within them.

The legal blogger David Allen Green also accused Hari of editing articles about himself and smeering others on Wikipedia.

Hari eventually had his 2008 Orwell Prize rescinded after the council reviewed the author's work .

Hari apologised for his actions, a move that also still managed to garner criticism. But he will now return to the Independent.

Chris Blackhurst defended the columnist, saying that Hari had not invented facts for hard news stories, and that while his actions were still serious he had learned his lesson.

"Johann did not believe he was doing anything wrong," Blackhurst told the Leveson inquiry.

Hari will return to the paper, however, after completing a media ethics course in New York, which he paid for himself.

"His reputation has been very very severely damaged," Blackhurst said. "The Independent's reputation in terms of Johann Hari has been severely damaged. He produced cogent reasons for why he did what he did. I don't think we covered up at all."

Blackhurst also denied there had been a cover-up, and said that he had been "enormously shocked" by the allegations.

"It was really profound and totally unexpected," he said.

Also giving evidence at the inquiry, the editor of the Financial Times Lionel Barber said that the phone-hacking scandal was a "wake-up call" that made British newspaper executives realise they must change how the industry is regulated.

Lionel Barber told the Leveson Inquiry into press standards that the revelations that culminated in the News of the World's closure in July amounted to a "shocking episode".

He called for the formation of a new independent press regulator with powers to impose fines, require corrections to be published prominently and launch investigations.

Barber told the hearing: "This has been a real shock, what happened at the News of the World, not just in terms of the extent, the industrial scale of phone hacking, but the pattern of lies.

"But also the result, which was shocking: the closure of a national newspaper with a circulation of several million, and a newspaper actually that has done in its own way over the years some very good stories - I am thinking of the fixing in the Test match.

"This was a shocking episode. All of us, I speak for myself, believe that as a result we need to change the way we do business.

"If this isn't a wake-up call, I'm not sure what is."