FLYING squads of tax inspectors would roam Northern Ireland after Brexit under an alternative plan drawn up by senior Tories to “destroy Chequers”, The Sun can reveal.

Arch-Eurosceptics believe a Hard Border with the EU could be avoided by “Inland Clearance” that would see goods made for export subject to spot checks from officials in factories and at arrival destinations.

2 The PM has been warned that she will face a catastrophic split if she pushes ahead with her Chequers plan Credit: Alamy Live News

It came as Tory backbencher Steve Baker said Theresa May faced a “catastrophic split” if she pushed ahead with her Chequers plan given more than 80 MPs are signed up to defeat the PM’s blueprint.

No 10 said critics of her plan had yet to come forward with a credible alternative which would avoid the return of a hard border between Northern Ireland and the Republic.

“Chequers is the only plan on the table which will deliver on the will of the British people while avoiding a hard border in Northern Ireland,” Mrs May’s spokesman blasted.

But plans drawn up by Dutch Customs Expert Hans Maessen with the powerful ERG group of Tory MPs say customs officials would be able to check goods while they are still “on the premises of the “importer/forwarder” rather than on the border.

2 Under their 'Alternative Chequers' plan, companies would have to declare the tax they owe on goods crossing the border with the EU Credit: EPA

MOST READ IN POLITICS EAT IN OR TAKE OUT? Chaos & confusion over whether cafes will HAVE to offer table service Exclusive RISHI BLOWS THE BUDGET Chancellor to extend furlough for staff worst hit by new covid rules WINTER COMING England may have to ban home visits too as SAGE adviser warns lockdown coming Latest DOWN TO BUSINESS Chancellor to launch 'furlough replacement' tomorrow as Budget CANCELLED Exclusive HEROES EQUAL George Cross IS on par with Victoria Cross rules Queen, ending years of debate LOCKED UP AGAIN New lockdown rules explained: Everything you can and can't do now

Under their “Alternative Chequers” blueprint, firms would be made to self-declare the tax they owe on goods crossing the border with the EU, as well as certify the standards and quality.

Then “mobile inspections teams” alongside “incidental inspections at the border” would make sure the rules were being obeyed.

The ERG have delayed publication of their alternative plan, but sources insist it will be unveiled in the coming weeks.

Theresa May addresses post-Brexit relations in PM's Gibraltar National Day annual message