When asked by the Business Committee if he would share the letter with its members, Greg Clark said he planned to release the letter once certain aspects which currently made it commercially confidential had passed.
"There are aspects that are commercially confidential, but they're not permanently so," Clark said.
Nissan surprised many back in October when it announced it would build two new car models, its Qashqai SUV and the X-Trail SUV, at its plant in Sunderland, securing 7,000 jobs in the process.
However, questions were quickly raised over just what, if anything, the Japanese company had been promised in the assurances it had been provided by government.
Andrew Tyrie, chair of the Treasury Committee, has called for Clark's letter to be put in the public domain, while the European Commission has also asked for more details on the deal to try to establish whether or not it breaches the rules for state aid.
Nissan had previously warned it might start to shift operations out of the UK if favourable tariff levels could not be secured as part of the Brexit deal.
Clark has previously said government reassured Nissan it would host "constructive" discussions with regards to tariffs when they arrived at the Brexit negotiating table.