In a concerted fightback building up to a lecture he is giving on Thursday evening, titled Devolution: A Process not an Event, Mr Davies insists the election pledge to create a Welsh Assembly was never part of "the project".

The former Welsh secretary was forced to abandon both his Cabinet post and his prospects of becoming Wales' first secretary after admitting a "moment of madness" following an encounter with a man on London's Clapham Common.

Ron Davies: "Serious issues to be addressed in Cardiff and London"

But he retains a strong following west of the border and recently won the backing of the Caerphilly and Cynon Valley Labour Party to contest the seat in the May elections.

'Cool about devolution'

In a pamphlet published ahead of his lecture at the Institute of Welsh Affairs in Cardiff, Mr Davies voices for the first time his discontent with the way Labour ran its devolution campaign.

"New Labour's advisers and apparatchiks were cool about devolution, seeing it as not relevant to 'the project', and a potential vote-loser in England at least," he writes.

"Neither before nor during the general election did we take our case to the people.

"In Wales we had one brief press conference at the start of the six-week campaign on our plans for the assembly.

"Although it was officially one of the party's election pledges, as far as Labour's national campaign was concerned Welsh devolution was a non-issue."

'Need to modernise Labour'

Mr Davies also warns of potential conflict when after the assembly election, when what he calls the devolution process really begins.

"There will be a number of very serious issues that will have to be addressed by the assembly and in Whitehall," he told BBC Radio 4's Today programme.

"The Labour Party is going to have to review its arrangements.

"We have to modernise the Labour Party's constitution, so that as we have devolved power in government terms we devolve power in party terms."

In his pamphlet, he adds: "Devolution is not a single defining event but a process.

"No doubt the assembly will have imperfections but it will change and adapt over the years, it will grow in confidence and stature, its power will increase and it will become the respected forum and authoritative voice of our country."

He hints that some key New Labour policies may no longer fit once the assembly has established itself in Wales.