Welcome to the inquiry. I'm Tanya Beckett. Each week one question four expert witnesses and an answer.

Hot on the heels of Britain's departure from the EU, London and Brussels are at

log-aheads over how to forge a new trading relationship. British Prime Minister

Boris Johnson wants a deal done by the end of 2020.

But some experts say that is way too tight a time frame.

After all, in the past, trade talks have been known to drag on for years.

The negotiations between the EU and UK come in the wake of a savage trade war between China and the United States,

which both countries are now trying to resolve.

Hammering out an agreement, though, is proving painstaking work. In this week's inquiry we ask why

our trade deals so hard to do.

Part Part 1, winners and losers.

There's a theory that anything that is in a children's book, you don't want to touch in trade negotiation.

So fishermen, farmers, train drivers.

Our first expert is Stephanie Ricard, a professor at the London School of Economics.

She says that when countries try to agree a trade deal, the journey is a long and tortuous one for many reasons.

But often a log jam can be traced right back to domestic politics.

If a government used their trade policy to protect sugar producers, that helps those producers,

they make more money, they have bigger profits, but it hurts food producers,

busy beverage producers, any business that uses sugar as an input good is disadvantaged.

So governments have to make that trade-off.

Who are we going to help with our trade policy?

Who are we going to hurt with our trade policy?

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