Keir Starmer, right, welcomes European Commission President Ursula von der Leyen and European Council President Antonio Costa to Lancaster House.Keir Starmer isn’t known as much of a gambler.The prime minister, a lawyer to trade, prefers to weigh up both sides of an argument before making a balanced judgment on his preferred course of action.But there is no doubt that the deal the government has today struck with the EU is a major risk – both economically and politically.British negotiators have spent the last six months in talks with their European counterparts, culminating in the agreement unveiled at Lancaster House today.New rules on veterinary and food products will, the government says, make it easier for British businesses to export their goods and reduce prices in the shops.In return, European fishermen will get access to British waters up until 2038 – far longer than had been expected.Greater co-operation on security will allow UK defence firms to bid for EU contracts, while Bri