Philip Hammond’s fiscal responsibility challenge might not be the most exciting intervention in the Tory leadership race but it has received a warm welcome from many of Westminster’s top think tanks. The Institute of Economic Affairs’ Kate Andrews says:

“The Chancellor has dished out a fair and sensible warning to leadership candidates. Slashing tax and spending increases must go hand-in-hand with cuts in other areas and a radical pro-growth agenda, otherwise they are not fiscally responsible policies…

“With the UK tax burden at a near-fifty year high, putting more money back in people’s wallets should be a top priority, but it shouldn’t mean abandoning fiscal responsibility along the way.”

The Adam Smith Institute’s Matt Kilcoyne welcomes the move too:

“Right message at the right time from the Chancellor. As we approach the Cost of Government Day on the 18th June, the first day of the year that private spending overtakes all the spending and borrowing the government does on your behalf, it’s good to see a Conservative preaching fiscal responsibility.

“The UK still has a deficit, a mountain of debt, and government is still passing the buck onto those too young to vote. The next generation shouldn’t be sold out with election pledges made at the expense of their own futures.”

The TaxPayers’ Alliance also give it their seal of approval:

“Philip Hammond is right that a Tory leadership battle isn’t the place for a public spending arms race. A spending spree by the current, or next Prime Minister could leave taxpayers saddled with bills.”

As far as Guido is aware, none of the candidates have committed to Phil’s fiscal responsibility pledge so far. Nor has the current Prime Minister shown any hint of reconsidering her uncosted trillion pound black hole she’s leaving behind for her successor…

UPDATE: It turns out Phil’s Pledge has been taken by the most left-wing candidate in the race, Rory Stewart. If Rory can find time out from his never-ending walks around supermarket car parks to make the pledge, why can’t any of his supposedly more Conservative rivals?