Premier League B teams and 'non-English' clubs will not be included in plans to reform the structure of the English Football League.
In May, it was revealed that the EFL, formerly known as the Football League before a rebrand this summer, could expand to include a fifth tier by 2019-20, with 100 teams over five divisions.
It is planned that additional clubs would come from the National League.
EFL clubs met to discuss the proposals for the first time on Thursday.
The exclusion from the plans, which will be voted on by all clubs in June 2017, of extra clubs from non-English leagues would appear to remove any prospect of Scottish giants Celtic and Rangers being involved in the EFL in the foreseeable future. Welsh clubs Cardiff and Newport already compete in the EFL.
Meanwhile, the idea to include Premier League B teams in any restructure which formed part of the Football Association commission's four-point plan to boost English football, has also been rejected.
"The logical place for many was to source the additional teams for League Three from the National League," EFL chief executive Shaun Harvey said.
"We will now continue our consultation with the National League with a little more certainty as to what any change could mean for them."
This season, the Checkatrade Trophy has included under-21 teams from Premier League and Championship clubs for the first time on a trial basis, something which the "overwhelming majority of fans" are against, according to the Football Supporters' Federation.
Why change the current system?
In May, the FA said the fixture schedule needed looking at "for the benefit of all" and the main aim of expanding to a five-tier league was to reduce fixture congestion.
The EFL believes the benefits of the possible expansion to five leagues, each consisting of 20 teams, include:
- Ensuring more games are played on weekends and Bank Holidays;
- Removing fixture congestion and clashes;
- Helping EFL clubs make more money;
- Keeping the play-off finals on the last weekend of the domestic season.
For the proposal to be approved, they will need the backing of 65 EFL clubs (90%) at next year's annual general meeting.
What does the proposed re-structuring involve?
The proposals are part of the FA's 'Whole Game Solution' and, as well as adding a fifth tier, centre around:
- The option of introducing a winter break
- Regionalisation of the lower divisions
- Changing the number of teams per division
In 2014, an FA commission's review also called for a ban on non-European Union players outside of the top flight and a reduction in non-home-grown players in Premier League squads.
What feedback did clubs give the EFL?
As well as rejecting the idea of including Premier League B teams and extra 'non-English' teams being added, clubs also gave the EFL feedback on the idea of introducing a winter break.
An EFL statement added: "The feedback has confirmed that clubs in League One, Two and the proposed League Three would want to play through a winter break if introduced."
Portsmouth chief executive Mark Catlin told BBC Radio Solent: "A lot of people's views have been taken on board by Shaun Harvey in the consultation. By taking [B teams] off the agenda, the EFL board have given themselves a greater chance of success.
"The other line in the sand as far as we're concerned is taking away our aspiration to compete in the highest possible tier - by cutting the Championship and other divisions from 24 to 20 teams, they're just never going to get our vote on that.
"One of the options that was brought to the table during the meeting was an option for no change at all.
"We like the existing structure, we like having FA Cup ties on weekends and we don't want a winter break or two Scottish clubs introduced."
BBC Radio 5 live sports news correspondent Richard Conway
"A radical revamp of the Football League structure was first proposed in May.
"The changes would see the introduction of a new 'League Three', resulting in 100 clubs in total within the professional pyramid.
"The big question for the EFL concerns where these extra clubs will come from?
"Today officials announced they will NOT be drawn from Premier League B teams or from Scotland. And that's significant given the reported interest from Rangers and Celtic in joining up with their southern counterparts.
"It also puts the final nail in the coffin on the B team debate, which first came to prominence in 2014 when Greg Dyke's much criticised commission of inquiry into English football reported its findings.
"It's a move likely to be welcomed by fans - the arrival of under-21 Premier League teams into the Checkatrade Trophy this season has been met with protest and boycotts by supporters.
"Negotiations amongst the existing 72 EFL clubs will now continue, with a planned vote on final proposals expected to be held next summer."
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