Companies doing deals in tax havens are facing tougher scrutiny from authorities, according to a survey by Ernst & Young, the professional advisory firm.

Deals involving low-tax jurisdictions were flagged for extra attention by about half of the 49 tax authorities across the world that participated in the survey. “Transactions with ‘tax haven’ jurisdictions ... are increasingly likely to be scrutinised and formal ‘watch lists’ are becoming more common,” it said.