Shahid Khan assured the FA Council before last week's meeting over the proposed sale of Wembley that the stadium would still belong to England.
Sky Sports News has obtained a letter sent by the Fulham and Jacksonville Jaguars owner to FA Council members.
Khan said under his ownership Wembley will be three things: "The National Stadium of England, the traditional home of English football and one of the world's finest venues for sport and entertainment."
The 68-year-old will also invest in Fulham's Craven Cottage this summer and drew parallels with calling the ground Fulham's "lifetime home".
He added: "As I've done with my investment in the NFL stadium in Jacksonville and we are about to see with Fulham and Craven Cottage, I will protect what we all agree is wonderful about Wembley Stadium and be steadfast, and respectful, in making sure the Wembley Stadium of the future will never have an equal. I owe that to the home of English football, to the FA, to London and to all of England.
"When I was privileged to become chairman of Fulham in 2013, I immediately encountered rumours as to what this meant for the future of our home ground of Craven Cottage and, for that matter, the Club itself.
"My word at the time was I would invest in the Club and the renovation of Craven Cottage so it would always be the lifetime and spiritual home of Fulham."
Khan outlined his plans for a new and improved Wembley and believes it could be unrivalled in the future.
He said: "Wembley Stadium must be the global standard in every sense - technology, hospitality, the visitor experience, the athlete expectation and much more.
"I will protect what we all agree is wonderful about Wembley Stadium and be steadfast, and respectful, in making sure the Wembley Stadium of the future will never have an equal."
Khan also added that he would like a committee of Council members to serve as advisors on all FA related stadium matters.
Thursday will be a critical day in the potential sale of Wembley as the Council meets to see the organisations blueprint to change grassroots football in England from money invested.
A full Council vote on the proposed sale is expected on October 24.