A £400 MILLION plan to privatise computer systems at Glasgow City Council has stalled after a blundering councillor hit the wrong button during a crunch vote.

Anne Simpson inadvertently sided with opposition parties by voting to send the controversial IT project back to the drawing board.

Colleagues have described the gaffe as “an honest mistake” but it has thrown the privatisation timetable into turmoil and could have financial repercussions for the cash-strapped council.

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The error ironically comes as Labour councillors face the threat of disciplinary action if they fail to attend committees or defy the party whip after ruling administration lost its majority when one of its members abruptly quit politics.

All eight Labour councillors turned up for the meeting on Monday but the mistake by Cllr Simpson, deputy chair of the Operational Delivery Scrutiny committee, meant the party suffered its first ever defeat.

Labour chief whip Cllr Alistair Watson, said: “Unfortunately Bailie Anne Simpson pressed the wrong button and realised this when the votes were counted. The chair concluded the meeting immediately after.

“Bailie Simpson intended to vote for the administration’s amendment but made an honest mistake.”

One Labour source said: “You’d hope that where any of our guys voted to stall this it would on ideological grounds, an act of rebellion against privatisation.

“Instead it’s ‘We don’t know what button to press’.”

The move now sees the previous plan to completely outsource all of the council’s IT to private firms referred back to the Labour-dominated executive committee for reappraisal.

Planned industrial action by Unison over the privatisation project scheduled for this week will still go ahead.

When asked to speak in favour of privatisation at Monday’s meeting, the council’s second most senior officer had said it would make the authority’s IT more resilient to industrial action as multi-nationals could bring in staff to replace striking workers.

The Herald revealed in August how the council planned to save £100m by privatising everything from payroll to schools IT and social work systems, with Canadian multi-national CGI the frontrunner.

The structure of the proposed deal has fuelled speculation all local government IT will be outsourced in the coming years, with Edinburgh and Borders already locked in a deal with CGI.

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Susan Aitken, leader of the council’s SNP group, said: “The administration failed to reassure SNP councillors over staff terms and conditions, the objectivity of the option appraisal process or the value for money of selling off the council family’s ICT silver.”

She added that the Labour administration should halt the IT deal and “put it to the people [at local government elections] in May”.

A council spokesman said: “Scrutiny is a normal part of the council’s committee process. The decision will be remitted back to the Executive Committee.”