Charles Green is facing a vote on his future at Rangers at an emergency board meeting, with the club's chief executive describing his conduct since arriving back at Ibrox as immoral and unethical.

Angry calls for the former chief ­executive to be sacked were made last night by fans as Craig Mather met more than 200 influential Rangers supporters. They had demanded the face-to-face showdown given the spiralling crisis at Ibrox and the sudden exit of chairman Walter Smith.

Mr Mather announced that a board meeting is to be called within the next seven days to discuss Mr Green's conduct and a vote will be taken on him remaining at the club.

Mr Green has, in a matter of days, been embroiled in a furious public row with manager Ally McCoist.

The Yorkshireman also issued an ultimatum to tycoon Jim McColl to stump up £14 million by the end of today for his consortium's shares or stay away from the club's affairs.

Mr Mather, who was originally brought into the Rangers fold by Mr Green as an investor and was appointed chief executive last month, spoke out about the consultant's treatment of McCoist.

He said: "I didn't agree with Charles Green. I don't agree with his behaviour and I don't think it's right. It's morally and ethically wrong."

Mr Green received an undisclosed payoff from the club when he left in April and now receives £1000 a month and is on a one-month notice period.

Mr Mather also revealed he will contact Mr McColl about his plans to force him off the board along with finance director Brian Stockbridge and non-executive director Bryan Smart.

Billionaire Mr McColl wants to bring former director Paul Murray and Frank Blin, a finance expert and former head of PricewaterhouseCoopers in Scotland, onto the board.

The tycoon has stressed he does not want to increase his small stake in the club or launch a takeover bid.

Mr Mather told fans last night that Mr McColl's plans needed to be fleshed out, but conceded that Mr Blin had an impressive record. The chief executive said he had no view on Paul Murray, the former head of the Blue Knights consortium, who has been involved in two attempts to buy the club since it went bust in February last year.

Mr Green claims he has raised around £34m for the club in three separate investment rounds since its collapse.

He has criticised club performance, high spending on players and the board's decision not to raise the cost of a season ticket this year by 10%, a move he claimed could have raised £2m for the club.

A spokesman for Mr Green, who returned to his home in France following Tuesday's match against Newcastle United, said: "Charles Green pleads guilty to the following crimes - saving the club from Craig Whyte and now trying to prevent it from falling into the hands of men who haven't invested a penny.

"Talk is cheap as Paul Murray and Frank Blin have repeatedly proved. Action costs more, more than the £2.80 invested by billionaire Jim McColl.

"As regards Mr Mather it is clear he is confused and intimidated by the fans' robust actions. Perhaps he should return to a much gentler business atmosphere. As for calling a board meeting to discuss Charles, perhaps he should ask his fellow board members before pushing the panic button. Glasgow is a place for big boys not frightened wee laddies."

The meeting was also attended by manager Ally McCoist, Mr Stockbridge and non-executive director Ian Hart.

Afterwards, shareholder Brian Bowman said: "The board should resign en masse. There were comments made tonight that were completely and utterly untrue. They told barefaced lies and we need to cleanse this club."

On Mr Green's future, he added: "I don't think they will sack him. After all, you can't sack the man who is paying the wages."

Drew Robertson, general secretary of the Rangers Supporters Association, said: "Hindsight is a wonderful thing, but hindsight has proved that it was perhaps the wrong decision to re-employ Charles Green."