The Football Association plans to slash its annual budget by £75million to tackle a possible deficit of £300million over the next four years due to the Covid-19 pandemic.
Chairman Greg Clarke also warned FA Council members in a letter published on the governing body's website that it would be some time before fans were allowed to attend matches again.
"The Board has agreed that a sensible cut to the annual budget is £75million," he said.
"In a worst-case scenario, this would be necessary for the next four years to offset a £300million pounds.
"Clearly that will impact many of our plans as every area of the game will be touched and projects that we all value will be affected. There is no other way and I ask for all of you to help us to build this revised plan."
The Council is next due to meet on 21 May.
"It's hard to foresee crowds of fans, who are the lifeblood of the game, returning to matches any time soon"
Professional football has been suspended since mid-March due to the new coronavirus pandemic which has killed nearly 28,500 people in Britain.
Premier League clubs held a conference call on Friday in which they looked at plans for a resumption of training later in May followed by a possible return to competitive action behind closed doors in June.
Events held at Wembley Stadium in 2018-19 generated income of £70.6million out of the FA's total turnover of £467million.
The FA also had broadcast income, from domestic and international rights to the FA Cup and England matches, of £262.6 million.
"The reality is that we just don't know how things are going to pan out, but with social distancing in place for some time to come we do face substantial changes to the whole football ecosystem," said Clarke.
"For example it's hard to foresee crowds of fans, who are the lifeblood of the game, returning to matches any time soon."