It is unsurprising that the people who prophesied doom and disaster if the UK voted to leave the EU are finding it so hard to instil confidence in the policy they never believed in. Whoever is the new Prime Minister must enter Downing Street ready with clear views to discuss with a new Cabinet and when agreed issue instructions for Whitehall to prepare to leave the EU swiftly and smoothly.

We owe it to the business community, and to our EU partners, to minimise the period and the disruption that is involved in leaving the EU.

We also owe it to the British people to deliver on the referendum vote, and not to cavil or delay taking back control over our laws, our borders and our financial contributions to the EU. That means starting to leave in a few months, not stretching it out for years, while discussing the transition within a democratic framework.

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The act of Parliament to give effect to our leaving the EU need only contain two key clauses. One will relieve the UK of all the obligations of EU membership.

Another will carry over all the EU law that currently applies to the UK into domestic law, so that at the outset, nothing changes at all.

The rest will be all about transitional arrangements. The new Prime Minister should have this legislation drafted and presented to Parliament immediately, so it can be enacted and ready to bring into force when needed. This should be on the Statute Book before the Christmas recess.

The reason why some seem to think this is so much more complicated is because they presume that we need to strike a trade deal with the EU before we start the transition to leave. This would be a massive strategic error.

While there are some non-trade issues which we will need to agree with the EU (such as the urgent matter of giving assurance to EU nationals resident in the UK and UK nationals resident in the EU, and replacing EU security policies such as the European Arrest Warrant and passenger data sharing with bilateral arrangements), we should not attempt to dictate the shape of any trade negotiations except to say we are ready to negotiate.

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The British people decided to leave on the basis that in future we would fully control our own borders, and it would be politically and socially explosive to renege on this. They were also promised we would put in place a points-based national immigration system and that would apply equally to all immigrants, whether from the EU or elsewhere.

The UK would essentially introduce a free trade policy while reserving the right to impose reciprocal tariffs. In due course, we might well be able to negotiate a UK-EU trade agreement (as the EU is seeking with the US, and already has with South Korea, for example), but the timing of that is not in our control, and the EU and the UK have to agree.

Fear of leaving the EU was based on myths about the Single Market, trade, trade agreements which must now be discarded. Leaving the EU means, as was clearly said in the referendum, being outside the Single Market. That is what the Leave vote means.

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We do not need to negotiate “access” to the Single Market. The UK’s biggest single trading partner is the US. They are our biggest single inward investor. But we have negotiated no “access” to each other’s markets. Neither the EU nor the UK currently has a trade agreement with the US. Some particular sectors like civil aviation require special treatment, but this shows how in general it is not urgent to negotiate “access” to the Single Market when we leave the EU. The UK and the rest of the EU will continue to trade with each other because it is in all our interests.

We should also avoid the risks of entering the Article 50 process to leave the EU before we are ready and before we have agreed what will be in the withdrawal agreement.

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This would be like signing a contract to buy a house, before you have agreed the price or done a survey. Article 50 was drafted to be obscure with the intention of making it difficult for a state to leave the EU. Maybe we can agree to use it as a means of exchange and completion of the transaction. The best agreement should be made as quickly as possible – with a pre-agreed exit date, at which point we also bring the EU repeal and carry over act into force.

If no acceptable agreement is forthcoming, then we just leave under our own laws. The Leave vote is not a conditional instruction.

Ideally, a withdrawal agreement itself should express the aspiration in Article 8 of good neighbourly relations and promote friendship, trade and cooperation between the UK and the EU, on trade, the environment, foreign affairs, security and defence, but not attempt to define a new relationship in one step. This is one which will evolve over time.

To propose a long period before we leave the EU is inviting the very economic uncertainty and chaos which any sensible European, in or out of the EU, wants to avoid, and does not understand the situation we are now in. Planning to compromise on the immigration question as a means of negotiating needless “access” to the Single Market, is to invite the ugly politics of intolerance and racism on to our streets. We must not let this happen. Instead we can embrace the new global freedoms and opportunities we can enjoy outside the EU without delay.