U.K. business leaders, resigned to a “hard Brexit” that many of them opposed, said Prime Minister Theresa May’s plan to leave the European Union’s single market at least provides them with some of the clarity they’ve been craving. May will say in a speech at 11:45 a.m. in London that she’s prepared to sacrifice tariff-free trade with the EU in return for the ability to curb immigration and assert Britain’s sovereignty, according to a person familiar with the situation. While that could hurt U.K. companies that do business in continental Europe, some have already written off membership in the single market and are focusing on the nuts and bolts of what happens after May triggers exit talks. “Businesses across the country over the last few months have been dealing with a lot of uncertainty,” said Marcus Mason, head of business, education and skills at the British Chambers of Commerce. “They will welcome some guidance on the kind of Brexit the U.K. is seeking.” With only weeks to go before May has said she’ll invoke the EU’s Article 50, formally setting the U.K. on the road to Brexit, executives have been grasping for details on Britain’s future trading relationships. Concerns have included the fall in the pound, access to migrant labor and the state of regulation.  Clean Break May will say she favors a clean break with the EU, rather than a “half-in, half-out” arrangement, according to extracts of the speech released by her office. She will be less definitive about the European customs union after Brexit, indicating a hybrid, partly-in, partly-out model may be the best option, according to the person familiar with the matter. “If you want to have greater control of immigration, if you want the ability to negotiate your own trade deals and you want to be outside the remit of the European Court of Justice, then you can’t be in the single market and the customs union,” said Paul Everitt, chief executive officer of ADS Group, an aerospace lobby organization. The group had urged U.K. voters to remain in the EU but Everitt nonetheless said he welcomed the “clarity on the realities of Brexit.” The Confederation of British Industry, which represents big business, has said its priority in the near term is a transitional agreement governing trade with the EU the day after the U.K. leaves the bloc. Without such a deal, the country risks a “disorderly crash landing,” CBI Director General Carolyn Fairbairn told the Guardian newspaper. The group declined to comment in advance of May’s speech. Small businesses are also hoping that the prime minister’s comments will end some of the uncertainty that has hobbled decision-making since the Brexit referendum last June, even as the economy has held up better than many analysts had forecast. “We welcome a steer as to what’s going to happen,” said Craig Beaumont, head of external affairs at the Federation of Small Businesses, in a phone interview. “Small businesses will operate in whatever framework is put on their plates.” Sector Details Others said they worried about an absence of sector-specific detail from May to see whether she will prioritize specific industries, such as car manufacturing or banking, during Brexit negotiations. Martin Sorrell, chief executive officer of advertising company WPP Plc, said the 12 principles May is said to be pursuing regarding Brexit are “a lot for a negotiation.” London-based WPP was opposed to Brexit and has been trying to grow its business in continental Europe since the June referendum. “I remain extremely worried about whether we’re going to maintain a really strong position in Europe,” Sorrell said in a CNBC interview at the World Economic Forum’s annual meeting in Davos, Switzerland.