The consequences have not been worked through by the league if the club is not sold by 31 May.
The comments were made at a Digital, Culture, Media and Sport session.
The UK government approved a special licence for the company.
The situation is extraordinary, complex and unprecedented, according to the policy chief of the league.
It is new to all of us.
The process of selling the club was halted after the UK government froze the assets of Russian billionaire Roman Abramovich because of his country's invasion of Ukraine.
On Tuesday, the EU imposed a travel ban and froze his assets.
A new licence will need to be issued for the London club to be sold, as a special licence granted by the government allows for the club to be fulfilled, staff to be paid and existing ticket-holders to attend matches.
McNamara said that the government has issued an operating licence which allows the club to function until the end of the season.
While there are grounds to allow that licence for this period of time, it can't be a thing infinitely while the club remains in Roman Abramovich's ownership.
If someone's assets are frozen but the league is able to fund them so that they can keep paying people, it's an exceptional thing to do.
The club are already up for sale so that process is quite mature. We are hopeful that a sale can be completed before the deadline.
Should the club not be sold by 31 May, what will happen?
She said that they were trying to manage the issues as they came across their desks.
Football can be managed perfectly well without Russian investment according to the UK Sports Minister.
There are plenty of other investors around the world that we can work with.
I cannot see how we will be able to welcome that money back for a long time.
I don't think it would be morally acceptable and we will still have sanctions imposed on many entities.
I don't think sport fans around the world and in particular in this country would find that acceptable. They have spoken loudly and clearly.
After the invasion of Ukraine,Everton suspended all dealings with Russian Alisher Usmanov's businesses, including his company USM's sponsorship of the training ground.
Russian football clubs and national teams have been suspended from all competition by world governing body Fifa and European counterpart Uefa with other sporting sanctions also in place.
The sanctions will last if Russia continues to be a pariah on the world stage.
They will last for some time and Russia won't be able to bid for major sporting events, so it will be quite a while before we accept Russia back into the world sporting stage.
A recent Saudi Arabia-backed takeover has caused controversy.
Eddie Howe was asked about the human rights record of Saudi Arabia after his side's defeat by the Blues.
The issue of club ownership was one of the issues looked at in the review.
The chair of the fan-led review proposed a series of measures to protect the future of the game.
Richard Masters said that the organisation is reviewing its owners and directors test as it had been under a lot of scrutiny.
The fan-led review is important. There are failures in the structure of English football.
If it was all working well, we wouldn't have needed a review.
There is a need for more robust owners and directors to be tested, and that is something that is being pushed.
Mark Bullingham questioned whether football should be held to a higher standard than other industries when it came to investment.
The top flight did not want a statutory independent regulator, but MacNamara pointed out that there was no owners or directors test when Abramovich took over.
She planned to take a revised version of the test to the clubs at the end of the month and at the annual general meeting.
We already have an independent panel, chaired by a QC, who oversee our sanctioning regime and we are in the process of putting together an independent panel that will support the league board and scrutinize their decision making.
If you talk to football fans fromLeicester City or Manchester City, they will tell you that the investment they have made in communities and schools is extraordinary. There is a lot of that.
The prospective new owners of the club were the subject of an open letter written by the Supporters Trust.
They ask for commitments on a number of fundamental issues, including a golden share for fans to protect key items of club heritage, and consultation with supporters through the creation of a shadow board.