BRUSSELS, April 19 (Reuters) - Apple's offer to open its tap-and-go mobile payments system to rivals is set to be approved by EU antitrust regulators as soon as next month after it tweaked some of the terms, people familiar with the matter said.

Apple's bid to settle the four-year investigation would help it dodge a finding of wrongdoing and stave off a potential hefty fine that could be as much as 10% of its global annual turnover. (Reporting by Foo Yun Chee; Editing by Jan Harvey)