A LEADING Tory has quit his senior roles in protest at Boris Johnson's plans impose a power grab on the devolved nations – saying it puts the Union at risk.

David Melding stood down today from his positions in the Welsh Shadow Cabinet - saying it threatened the UK's survival as a four nation state.

The former shadow counsel general and culture spokesman also cited his unease over provisions in the internal market bill to override EU withdrawal agreement – which the UK government admitted on Tuesday broke the law.

"The publication today of the Internal Market Bill has done nothing to lessen my anxieties about the dangers facing our 313 Union," he wrote in his resignation letter.

"Indeed they have been gravely aggravated by the decisions made in the last few days by the Prime Minister. Indeed it is clearly not feasible for me to continue in my post as Shadow Counsel General while holding such reservations.

"Furthermore I believe it is time to step down from all my shadow cabinet responsibilities as I will feel it necessary to speak out against what I consider to be a lack of statecraft at this crucial time for the UK's survival as a multi-national state."

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Scottish Tory leader Douglas Ross has defended Johnson's plans saying they were "small clarifications" of the agreement.

Ross claimed during an STV interview on Monday that a No-Deal Brexit could offer "great benefits" to Scotland and suggested plotting to renege on the withdrawal agreement was "responsible".

Asked about Johnson’s plans to renege on the agreement, the Scottish Tory leader commented: “I think Number 10 and the Prime Minister have been very clear that these are small clarifications that are effectively a safety net, we are still continuing the discussion with the joint council and European Union, but it is right that we prepare for all eventualities and it’s important that these small corrections and clarifications are in place to preserve the peace that we so rightfully cherish in Northern Ireland.”

The Moray MP added that plans to override the customs deal for Northern Ireland in new legislation are “responsible”.

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The SNP's Deputy Westminster Leader, Kirsten Oswald, said: "Even Tory spokespeople can't abide Boris Johnson's power grab bill, which would roll-back devolution and enable Westminster to overrule the Scottish Parliament and Welsh Senedd.

"This shameful bill would not only break international law but it would also dismantle the foundations of the devolution settlement - and the SNP will oppose it every step of the way.

"The Scottish Tories must come out of hiding and join parties across the Scottish Parliament to oppose this attack on devolution. Otherwise it will prove yet again that Douglas Ross and his Tory MPs are incapable of standing up for Scotland and will rubber stamp any order from Downing Street no matter how damaging to Scotland.

"Scotland has been completely ignored by Westminster throughout the Brexit process - and we now face an extreme Brexit and attack on devolution imposed on us against our will. It is clearer than ever that the only way to defend the powers of the Scottish Parliament and protect Scotland's place in Europe is to become an independent country."

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