The Silk commission jigsaw and Danny's diary marker

It is, according to the Treasury chief secretary, the last piece in the Silk jigsaw. (They'll be having Silk tea towels and mugs next).

Ministers in the coalition government can't agree whether control of stamp duty land tax should pass from Westminster to Wales, so they will consult industry on the proposal contained in the Silk commission report.

The (Liberal Democrat) Chief Secretary, Danny Alexander, clearly wants to finish the jigsaw. The (Conservative) Welsh Secretary, David Jones, is rather more cautious and could probably cope if there were one or two Silk recommendations that got lost behind the sofa.

Labour see the consultation as a delaying tactic, arguing that business has already been consulted. The UK government argues that consultation was confined to Wales and didn't assess opinion over the border.

The consultation may or may not ease coalition tensions on the issue but one question stands out: what happens if the conclusions agree with one half of the coalition. Does the other half back down?

Mr Alexander announced the consultation in a written ministerial statement to parliament here. Note the reference to "early access to borrowing" to enable the Welsh government to pay for improvements to the M4. This follows a similar move in Scotland, where a system of "pre-payments" has allowed Holyrood ministers to access finance before the Scotland Act comes into force.

Given the delay in the UK government responding to the Silk report - originally promised by the end of Spring - I asked Danny Alexander to clarify when autumn finishes in the Treasury calendar.

"September or October" came the reply. Make a note in your diaries now.