It had been expected that the report's compromise proposal for the supplementary vote - 'a single member constituency majoritarian system' for Commons elections - would be accompanied by publication of the report and a press conference with John Smith, the Labour leader.
Instead, Mr Smith issued a two-page statement, in which he said he remained 'unconvinced of the need for a change in the system of voting for the House of Commons', while offering a referendum on the issue.
'I see no reason why we should make a change unless the alternative is clearly preferable,' he said. 'However, I firmly believe that the contents and conclusions of the Plant report merit the widest possible debate both within and beyond the Labour Party.'
Copies of the report were not issued with the leader's statement and a working party member protested yesterday that they were still not generally available. 'They're deliberately sitting on them,' he said.
A party press officer said she did not know when the report would be released. She said later: 'We have decided that we're not publishing it officially, but it is available on request.'
Clare Short, a member of the national executive and also of the working party, said last night: 'It appears that the press office is making it's own policy on this matter. I will be making inquiries.'
The Plant Report, a copy of which was leaked to the Independent yesterday, said: 'What is really vital is not so much that our recommendations should be regarded as the final word on the subject, but rather that, as far as possible, all members of the party should become involved in the debate.'