DOWNING Street has given a cast-iron guarantee that David Cameron will honour his commitment to give Scotland more powers "no ifs, no buts", risking a backlash with Tory right-wingers in England.

A senior No 10 source, responding to fears the Prime Minister had "tricked" voters by linking extra powers for Scotland to more devolution for England, made clear one was not conditional on the other.

"This will happen come what may. We are absolutely clear; Mr Cameron is not reneging on his commitment to Scotland," he said.

In the aftermath of the referendum vote, political heat continued to be generated with the suggestion Mr Cameron wanted to link more powers for Scotland with giving England more devolution following pressure from Conservative MPs.

After his much-publicised more powers "vow" alongside Ed Miliband and Nick Clegg,Tory MPs hit out.

Yesterday, David Davis, the former leadership contender described it as "disgraceful" and "panicky".

UK Justice Secretary Chris Grayling said Holyrood should not get more powers while Scottish MPs could still "shape the destiny" of the NHS and schools in England.

Today, the PM has invited some of his most vocal backbench Tory critics to an "English votes for English laws" summit at Chequers, seeking to head off a potential rebellion.

In a round of interviews, Mr Salmond went on the attack, claiming Scots had been duped by the three-party pledge on more powers.

He said that the timetable for delivery was slipping "shamelessly" because Mr Cameron could not guarantee the support of his backbenchers, who wanted more powers for English MPs.

The FM insisted those most incensed by the reneging of the pledge would be No voters, warning: "The wrath of Khan will be as of nothing to the wrath of a No voter who has been gulled by the Westminster leadership."

But earlier Mr Miliband was adamant the agreed timetable - draft legislation by January and implementation after the May General Election - would be adhered to, saying: "We are going to deliver on that promise, no ifs, no buts."

Alistair Darling, who led the Better Together campaign, described the three-party pledge as "non-negotiable", warning that anyone who welched on the deal would pay a heavy price.

Privately, Labour sources were incandescent.

One Miliband aide said: "Cameron now has to do the right thing and get this sorted out.

"He cannot start playing political tricks."