May to announce that all EU law is to be kept on Brexit and only gradually reviewed and repealed

It's Brexit day tomorrow at Tory Party conference - and in her first speech to delegates as their leader and PM, Theresa May feels she must say something substantive.

She obviously cannot lay down what she would like our future trading relationship with the EU to be, because the cabinet is completely split on that.

But I do expect her to make an important announcement - about the status of EU laws and regulations after we actually leave the EU.

What I expect her to say is that there will be legislation here to enshrine in British law all laws and regulations stemming from our membership of the EU and single market.

In other words, leaving the EU would not lead to a single EU law or regulation being abolished at that instant.

The plan would be to abolish unnecessary laws and regulations over subsequent years.

The reason for this so-called "grandfathering" of EU law would be to reassure the private sector that they know what is and is not lawful in respect of how they make their products, how they do their deals and how they employ people.

And Theresa May also wants to reassure employees that their jobs would not become any less secure as a result of leaving the EU.

The Prime Minister wants to assure people - like those in the city - their jobs are safe. Credit: PA

There may be some of her colleagues who lobbied for Brexit who will see her decision to initially preserve all these EU laws as a betrayal.

But she will point out that on leaving the EU no new laws and regulations would be imposed (unless against the odds we remain members of the EU single market).

"It would be the end of the great flow of EU red tape" said one of her colleagues.

And the prime minister will also say that in subsequent years British governments and other governments can review the stock of inherited EU laws and amend or appeal what they don't like.

We'll know tomorrow whether the Tory party is angered or reassured that decades of law from Brussels is here to stay for many years.

And I will be putting the question whether May is betraying the Brexiteers to one of their leaders, Chris Grayling, on Peston on Sunday tomorrow at 10am (and repeated at 10.20pm).