Welsh ministers have taken the first steps towards a referendum on devolving more powers to the Cardiff administration.

Rhodri Morgan and Ieuan Wyn Jones announced that Sir Emyr Jones Parry will become chairman of a convention on devolution.

The body will promote understanding of greater self-government in the run up to a referendum held no later than 2011.

The move could see the Welsh Assembly Government and National Assembly for Wales take on the same powers as the Scottish government and Scottish Parliament.

Under the latest legislation passed by Westminster, devolved ministers have already seen their powers enhanced.

But approval is still needed from London for specific new powers to implement policy changes in Wales.

A referendum on a move to Scottish-style devolution within the next four years is part of the 'One Wales' coalition agreement between Labour and Plaid Cymru.

The first minister said Sir Emyr would not campaign for a 'yes' vote in the referendum, but would help "build the foundation in civil society by promoting understanding of it".

Jones, Plaid Cymru leader and deputy first minister, said: "We are very pleased that the appointment has been made and we will see the convention starting its work seriously in the next few weeks and certainly at the start of the year."

The Conservative leader in the assembly, Nick Bourne, said there "should have been some discussion" about the appointment before it was announced.

"I have been trying to get a leaders' meeting for the best part of a month with that on the agenda," he said

"The fact there's a large majority on the government side should not be used to railroad things through."