A Conservative metro mayor has called a Labour MP a “liar and a coward” as the feuding over a huge regeneration project became increasingly acrimonious. Ben Houchen, the mayor of Tees Valley, made the claims against the MP for Middlesbrough, Andy McDonald, during a combative radio interview on Wednesday. McDonald had previously used parliamentary privilege to allege “industrial-scale corruption” around the Teesworks redevelopment of the former Redcar steelworks, a project taking place in the UK’s largest industrial zone. Michael Gove, the levelling up secretary, last week ordered an “independent review” into allegations of “corruption, wrongdoing and illegality” around the redevelopment. Its backers say it will create 20,000 jobs on an area that is Europe’s largest brownfield site. Accusations of croneyism and corruption have been made after reports in Private Eye and the Financial Times about contracts and land agreements. Speaking to BBC Radio 4’s World at One, Houchen accused McDonald of “lying” and “abusing his parliamentary privilege” to make allegations of corruption. “Andy McDonald is a liar and he’s a coward. He would never repeat those accusations outside of parliament because he is a liar,” he said. “The reason for the investigation is because Andy McDonald lied and said that there was corruption. He has no evidence, he’s produced no evidence – he didn’t even give any examples or evidence within parliament.” Houchen said he was “1,000%” confident the independent review would show that the Tessworks project was a good one for the people of Teesside and the country as a whole. “I’ll be calling for the Labour party to reimburse the taxpayer for the waste of time that this review ultimately is, because it’s going to show there is no corruption, no illegality and criminality,” he said. The presenter, Sarah Montague, made an appeal for McDonald to come on the programme to respond to Houchen’s remarks. Twenty minutes later McDonald did just that, although he declined to repeat the “industrial-scale corruption” claim that he made in parliament. “This doesn’t pass the smell test, any of it,” he said. “There are so many elements to this that warrant very close scrutiny and investigation.” Asked if he would repeat the comments outside parliament, the MP said: “Well, I’m quite happy to sit down with Ben and go through my concerns with him.” Told that it was interesting he would not repeat the accusation, McDonald said Gove had set up an independent investigation that will “opine on these various elements”. If it finds the procurement process has not been a proper one, McDonald said, then people will say “this is not right, this is not the way business should be done and it has been a failure of governance and process”. Asked if the language he used was wrong, McDonald said: “I think it has gained attention for these very serious issues that have been raised by Private Eye and by the Financial Times, and I think hitherto the government has been quite happy to go along with the hard hats and promises approach of Ben Houchen and just say: ‘Nothing to see here.’ “There’s a great deal to see here.” Labour had wanted the National Audit Office (NAO) to investigate Teesworks. Gove, however, said it was not the NAO’s normal role and will instead appoint a panel himself.