The Government will not publish the letter it sent to Nissan which led to the car manufacturer's decision to pour new investment into its Sunderland plant, Greg Clark has signalled.
Ministers have been under pressure to reveal the terms of its agreement with the Japanese car giant following last week's announcement that the company will build two new models at its plant in the north east, securing the future of 7,000 jobs.
The Business Secretary set out details of the Government's four-point approach to the automotive sector, including Brexit reassurances, in a letter to Nissan chief executive Carlos Ghosn.
But Mr Clark suggested to MPs he will not publish the letter due to the need to protect Nissan's commercially sensitive investment plans.
The Government has strongly denied suggestions it offered the firm a "sweetheart deal".
Mr Clark told the Commons the letter contained commitments to continue to make funds available for skills and training, to encourage smaller firms in the supply chain to locate in the UK and to support research and development.
It also contained a pledge to keep the UK car industry competitive post-Brexit.
Labour's shadow business secretary Clive Lewis demanded that the letter be published. The SNP have also submitted a Freedom of Information request asking for the letter to be made public.
But Mr Clark said: "You asked me whether I would publish the correspondence.
"I have set out the information that I gave them and I would just say this to you.
"My responsibility, on behalf of the Government, is to encourage and to attract investment in this country and it's important that when companies of all types and in all sectors share with me their investment plans that are of information to their prospective competitors that they can be assured that they are not going to be disclosed to their competitors to their disadvantage.
"My objective is to obtain those investments but I'm very happy to answer today and to the select committee where I intend to appear at the invitation of the committee all of the aspects of it."