Editorial Comment and David Laws:

Our time spent in coalition showed Mrs May’s qualities – and she’ll need every one of them in the days ahead

So, article 50 has been triggered. The serious negotiations now begin. What can the people of the UK, and indeed the governments of the other 27 EU nations, expect from Theresa May as she goes in to bat for Britain?

During the Coalition government I often had to negotiate with leading Conservatives, including Mrs May. What did this experience tell us about how she is likely to play her cards?

Well, first, we know that Theresa May is no pushover. She was tough to negotiate with – and not just in her relations with other political parties. To Ken Clarke she is “that bloody difficult woman”; to Nick Clegg she was the “Ice Queen”; Eric Pickles referred to her (behind her back!) as “Tricksy Belle of Marsham Street.” I was told that she and Chris Grayling (then justice secretary) fought like “two scorpions in a bottle”. And even David Cameron had his own private nickname for his home secretary, which nodded at her metallic and unengaging character. In talks, she was always professional and formal – Nick Clegg once observing after one particularly difficult meeting that “she has no small talk, absolutely none. Cameron says she’s exactly the same with him.”

Don’t expect Mrs May to rush to do her deals either. In the first Coalition Spending Review, in May 2010, she was the very last Cabinet minister to settle her department’s budget with me – quite literally at 10 minutes to midnight. When talking to Conservative ministers before their annual party conference, I often found that the then home secretary was still battling with David Cameron over the contents of her speech just hours before the conference was due to start.

But if Mrs May is no pushover, it should not be assumed either that she is inflexible, unimaginative or intransigent. Although she is regarded as a Right-winger politically, she is a person who listens to argument and is interested in “what works”. In government, I found that Mrs May generally approached issues with a steely common sense and pragmatism which made her one of the less predictable of the senior Conservatives. In negotiations she was also capable of understanding that she needed to rethink her strategy when she could not persuade others of her views. After another tough meeting with Nick Clegg, he observed: “She is instinctively very rigid, but you can be tough with her and she’ll go away and think it all through again”.

Mrs May is also a person who is direct and straightforward to deal with. She generally avoids the silly political games which are designed to look clever, but which can often only irritate opponents. And she is rarely attracted to political and policy gimmicks, which win one day’s favourable media coverage, but unravel shortly after.

Finally, this piece of advice: Mrs May is not one of the world’s great delegators. In government, she probably shared information and responsibility less with her Liberal Democrat and Conservative colleagues than in any other part of government. So forget Boris Johnson. Forget David Davis. Forget Liam Fox. This will be Mrs May’s negotiation and she – and only she – will speak for Britain.

If all this sounds pretty positive, so far, it is. Accepting the result of last June’s referendum, the UK and its Conservative Government is now led by a tough, pragmatic, thoroughly grown up, hard-working, conscientious former “remain” voter, who avoids idiotic anti-EU rhetoric and has not pretended to have suddenly converted into an ardent Brexiteer, but who clearly believes that there is a pragmatic deal to be done.

So far, so good. But Mrs May has also been forced, by her own party and her interpretation of last June’s public vote, into a fairly hard form of Brexit, which will considerably weaken her negotiating clout with other EU nations. She will find herself at the negotiating table with few cards to play and with few natural allies. Indeed, many of the other EU nations will want to steal British business opportunities, and some may even want to make an example of Brexit Britain. It is unlikely that a few not-so-subtle threats about ending UK cooperation on crime and security will win much influence or many votes.

What Mrs May should have learnt from the Coalition about negotiating is that “No” is a more powerful word than “Yes.” You cannot force other independent parties to do things in negotiations unless you have cards to play – something valuable to give up or to withhold.

When Mrs May tried to persuade an unwilling Nick Clegg to sanction a UK “Snooper’s Charter”, ultimately the deputy prime minister said “no”, and that was the end of the matter.

So we are sending to Brussels a steely and highly effective negotiator, with a rotten hand of cards. Mrs May will need to be much more than a “bloody difficult woman” to pull off the deal she wants. She will need charm, flexibility and great shrewdness if she is to avoid an outcome which would be as disastrous for Britain as for her own political legacy.