Manchester United executive vice-chairman Ed Woodward said Project Big Picture was "not a behind closed doors power grab" at a recent fans forum meeting.
PBP, which United and Liverpool helped develop, included proposals for a significant reshaping of English football, and a £250million rescue package for EFL clubs to boost them amid the coronavirus pandemic.
There was criticism of the project for appearing to concentrate too much power in the hands of the 'big six'.
Details became public on October 11, and three days later it was unanimously agreed by Premier League clubs that they would not endorse the plans, as they instead continued work on a "strategic plan" involving all 20 teams.
A proposed £50m rescue package for League One and League Two was rejected by EFL clubs in mid-October, before it was announced on Thursday that the Premier League and EFL had agreed a £250m package.
Speaking at the fans' forum event on November 20, minutes from which were posted on United's website on Thursday, Woodward said: "We have been pushing the rest of the Premier League to provide emergency assistance to the EFL on a no-strings-attached basis and we will also remain at the forefront of discussions about reforms to improve the long-term financial sustainability of the entire English football pyramid.
"A strong Premier League and a financially sustainable and robust pyramid are both crucial to the health of the national game and that's the principle we will continue to pursue within the strategic review recently launched by the Premier League.
"Those objectives were at the heart of our involvement in Project Big Picture. It's important to reflect that this was a work in progress. It was not a behind closed doors power grab; only draft proposals and a discussion document.
"The next step would have been to roll them out to all stakeholders in search of consensus."
Woodward also spoke about United being "at the centre" of discussions about the future of European club competitions, saying: "Most of my time in this regard is focused...on the strengthening of existing UEFA club competitions.
"The dialogue focuses on them continuing to be predominantly midweek games having little or no impact on the Premier League. We believe that any changes to European competition post-2024 must be complementary to thriving domestic leagues.
"Other domestic leagues feel the same way, reflected in conversation with our counterparts in other clubs and countries. We expect progress with UEFA through the ECA (European Club Association) to be made in coming months."
Fans have begun to return to some stadiums on a limited basis this week after the country entered a tier system again, although games at Old Trafford – as a tier three venue – remain behind closed doors.
Woodward said at the fans forum that United were "confident in our ability to host fans in a safe, socially-distanced environment once we get the go-ahead."
Woodward also stressed the belief there was at the club in boss Ole Gunnar Solskjaer.
United's most recent game had seen them bounce back from defeats to Arsenal and Istanbul Basaksehir with a 3-1 win at Everton – they have subsequently beaten West Brom, Basaksehir and Southampton before losing 3-1 to Paris St Germain on Wednesday.
"We recognise there's more hard work ahead to achieve the consistency needed to win trophies," Woodward said.
"But we see positive signs on the pitch and the training ground that reinforce our belief in the progress being made by Ole, his coaching team and the players."
He added: "I told this forum in April that we remained committed to strengthening the squad, while being disciplined in our spending during the pandemic.
"I believe we've delivered on that, with the additions we made during the summer taking our total net spending to over 200m euros (£180m) since summer 2019 – more than any other major European club over that period.
"We will continue to support Ole with a planned, long-term approach to recruitment, focused on the summer windows."
