Millions of U.S. expatriates may pay less tax as Republicans eye the elimination of requirements for citizens abroad to pay taxes both overseas and in the U.S., the Financial Times has reported, citing House Ways and Means Committee chief Kevin Brady.

Lawmakers were taking "seriously" calls for a shift from a citizen-based income tax system to one that is residence-based, with people taxed only on income earned in the U.S., the paper quoted Brady as saying.

Republicans have already decided to make an equivalent change for businesses, switching to a territorial regime that puts U.S. corporations' foreign earnings beyond the reach of American tax collectors, the FT said. Some 8.7 million Americans live outside the U.S., excluding military personnel, according to the Association of American Residents Overseas, the newspaper said.