They say the drive to involve private firms in rescuing failing schools could be at risk if the government fails to give a clear lead.
Surrey is waiting for the formal go-ahead for its proposals to draft in 3E's Enterprises to run the troubled King's Manor comprehensive school in Guildford.
The formal period for objections to the plan, which involves closing King's Manor and reopening it as an art and technology college, ended on Wednesday.
But Tory education spokeswoman Baroness Blatch told the House of Lords the whole scheme was being 'subjected to inordinate delay' by Mr Blunkett.
She quoted Surrey education chairman and Tory member Dr Andrew Povey as saying if ministers did not clarify the position without more delay, 'the whole drive to involve the private sector in turning round failing schools would founder'.
Government education spokesman Lord Hunt refused to give a government view on the fate of Surrey CC's proposals.