The IRS and U.S. Treasury must write regulations to clarify some complex provisions baffling individuals and businesses.

Everyone is struggling to understand the implications of it because of the novel and complex provisions that were introduced, says Roche.

Some Democrats also were unhappy that the bill contained complex provisions that went straight to the floor without the ability to offer changes first.

The new Treaty is a lengthy document, full of amendments to the existing EU Treaties and with complex provisions which even experts may find obscure.