Theresa May, U.K. prime minister, casts a shadow on the wall of the podium at the Conservative Party's annual Spring Forum in Cardiff, U.K., on Friday, March 17, 2017. May will pledge to forge a closer union within the U.K. in a rebuke to Scottish National Party leader Nicola Sturgeon, who started the week calling for a new independence referendum for Scotland. Photographer: Simon Dawson/Bloomberg via Getty Images