As turmoil over the British exit from the European Union deepens, the Securities and Exchange Commission is looking for public companies to start disclosing more about how they’ll be affected.

At a Financial Executives International conference, SEC Chairman Jay Clayton said he believes there’s a great deal more companies could be telling investors about how they’ll be affected by Brexit, and it will be a focus for the SEC going forward. “My personal view is that the potential impact of Brexit has been understated,” he said. “Those impacts will start to manifest themselves” before the United Kingdom officially cuts ties with the European Union, he said.

Wes Bricker, chief accountant at the SEC, said companies likely will see effects from Brexit to their integrated supply chains or integrated financings around the globe, which would affect assumptions that go into asset valuations and financings, among others. It’s an area of disclosure “that has come along,” said Bricker, but the staff will especially be watching for more robust disclosures at year end.

Party leaders in the United Kingdom are still trying to work out a blueprint for the British exit from the EU, which is scheduled for March 29. Brexit proponents face a mid-January deadline to place a plan before Parliament. Recent survey data suggests only about half of companies have developed their contingency plans to prepare for Brexit, and only a tiny fraction have carried out their plans.

The SEC has seen a wide variety of disclosures in public filings to date, said Clayton. On one end of the spectrum, he said, even within the same industry, some companies are providing “a fairly detailed discussion” of how management is viewing and assessing Brexit and its effect on their business. At the opposite extreme are companies disclosing “what I would say is a macro policy statement that Brexit is coming and it portends risk,” said Clayton.

The SEC staff is looking to move more companies along the continuum toward more detailed discussions that give investors greater understanding of what’s coming, said Clayton. He wants to see disclosure, “to the extent it is material and appropriate,” that gravitates toward more specificity, he said.