The Welsh Secretary is sympathetic to extra powers for the assembly

His comments during a BBC Wales interview follow the controversy of Tony Blair's constitutional reforms, which made the Welsh Secretary's job part-time.

But the new Leader of the Commons has denied that more constitutional change is now inevitable.

At the same time, Assembly First Minister Rhodri Morgan has said the new set-up was not his "most preferred" option for Wales' representation at Westminster.

Neath MP Mr Hain is set to make a speech in Cardiff on Friday night to argue for a higher rate of income tax, compulsory voting at general elections and further modernisation of the House of Lords.

But his comments on Assembly powers is set to add fresh impetus to the debate on the structure of devolution since Tony Blair's cabinet reshuffle.

Mr Hain said nothing has changed, but added he will carefully consider arguments for further constitutional change.

Rhodri Morgan says the new set-up is not his preferred option

Speaking on BBC Wales' Dragon's Eye programme, he said: "I stand where I have always stood.

"If a solid and worthwhile and well-argued case is put for increased powers, which will show better delivery for the people of Wales, and shows something can't be done through the present system, then I'll look at that with a very sympathetic eye."

Meanwhile, Mr Morgan has launched a stinging attack on Downing Street press officers, blaming them for confusion which followed the cabinet changes.

In the hours immediately after the prime minister's decision to make the Welsh Secretary's post a part-time position, Downing Street said the Wales Office was to be abolished.

Spokespeople for No 10 said the Wales Office would become part of the new Department for Constitutional Affairs, under Lord Falconer.

Angry response

The following day, Mr Hain emphatically denied the Wales Office had been abolished but admitted the constitutional reforms could have been publicised more effectively.

In an interview on BBC Radio Wales to be broadcast on Friday evening, Mr Morgan has picked up on this theme.

He said the handling of the reshuffle by Downing Street press officers "did not represent the highest standards of professionalism that you expect - they went AWOL".

Mr Hain's comments on a new top rate of tax have already brought an angry response from the Treasury.

A spokesman said: "It is the chancellor in budgets who makes decicison on taxation.

At no point has Peter Hain raised these issues with the Treasury."

The spokesman said the government would continue to honour its manifesto committment not to raise the top rate of income tax.