She said: "Of course Brexit was not the only reason but it was pretty prominent in Nissan's decision".
"The government fully recognizes the significance of the European Union market to your presence in Sunderland", wrote business minister Greg Clark to then-CEO of Nissan Carlos Ghosn.
The newspaper said the letter contained comments by Mr Clark that it would be "a critical priority of our [Brexit] negotiations to support United Kingdom auto manufacturers".
The report comes a day after Nissan said it was going to make the X-Trail in Japan instead.
Nissan, the Japanese automaker giant would be pulling themselves back from manufacturing the next models of their X-Trail Sports utility vehicle in United Kingdom, ahead of a boorish Brexit, which could potentially hurt the manufacturing cost and jeopardize the future of the vehicles, aimed at exporting in to the European Union nations, a Sky News report revealed on Saturday, the 2nd of February, 2019. The company also said it is increasing spending on new powertrains for future European vehicles.
"Grant support for training and development and environmental improvements were applied for and authorized ... on the basis that both the Qashqai and the X-Trail models would be built in Sunderland", Clark informed parliament.
"Therefore the company has made a decision to optimise its investments in Europe by consolidating X-Trail production in Kyushu".
The Nissan factory builds around 30% of the UK's 1.52 million cars, making it the largest auto factory in the country.
"The letter, written in October 2016, shows Nissan and the UK Government's continued desire to support investment in the UK and maintain Sunderland as one of Nissan's manufacturing hubs in Europe", the company said on Monday.
However, earlier this week it confirmed a decision to move production to Japan. Brexit uncertainty has since prompted consternation in some boardrooms in Tokyo.
"Unite will continue to press for further long-term guarantees over future investment and new models to secure the site's future for generations to come", said acting national officer for the automotive sector Steve Bush.
Nissan has become the latest corporate big-hitter to slash investment in the face of heightened economic uncertainty and a potential no-deal Brexit.
"Should it be a hard Brexit, I would not be surprised if also the decision to produce the Juke and the Qashqai might be re-examined", he told AFP.