O'Neill says Celtic and Rangers would be a hit in the Premier League
Aston Villa manager Martin O'Neill says the English Premier League would benefit from the inclusion of his former club Celtic and rivals Rangers.
The proposal to create a two-tier Premier League could be discussed at the league's AGM in June.
And O'Neill, who left Celtic in 2005 after five years in charge, said the Old Firm would be a hit in England.
"My personal thought is that Celtic and Rangers would enhance the Premier League," he told Villa's website.
Last week BBC Scotland learned Bolton chairman Phil Gartside has proposed allowing the Old Firm clubs to move to England as part of a two-tier Premier League of 18 teams each.
The idea would have to overcome a number of obstacles if it was to come to fruition, and Uefa's director of communications William Gaillard told BBC Scotland the matter would be something to be decided between the leagues and associations involved.
O'Neill believes the Glasgow clubs would grow if they were given the green light to play in England.
I'm not sure about Rangers but I know Celtic's capacity could go from 60,000 to 80,000 overnight - without a doubt
Aston Villa manager Martin O'Neill
"Glasgow is a phenomenal football city - Celtic house 60,000 and Rangers house 50,000," he told Villa's website.
"I'm not sure about Rangers but I know Celtic's capacity could go from 60,000 to 80,000 overnight - without a doubt.
"When I was manager of Celtic a number of years ago, there was some talk of both teams joining the Premier League in some capacity.
"There was mention of them being put in the Championship too, or maybe even lower down than that, and then making them work their way up through promotion."
He added: "If forced to do that, they would eventually get to the top and end up as monumental players in the Premier League."
O'Neill said he was aware sceptics would be against the move, but he believed the clubs would enhance the competition in England.
"I suppose Belgian teams could then ask to join the Dutch league and Dutch teams could then request to join the Bundesliga," he went on.
"All of those points would have to be considered. But if you're asking for a personal opinion, I think Celtic and Rangers joining would enhance the Barclays Premier League and make us all strive to get better.
"I certainly support the idea. But, then again, I could be a voice in the wilderness."
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