The top U.S. Senate Republican said on Tuesday he would unveil a revised version of major health care legislation sought by President Donald Trump on Thursday but deep divisions within the party left the stalled bill's prospects uncertain.

Majority Leader Mitch McConnell said the Senate would take steps to begin debate and hold a vote on the reformulated plan next week, but did not disclose any of the changes to legislation that some Republican moderates and hard-line conservatives have opposed.

McConnell also pushed back the Senate's planned August recess by two weeks to allow senators more time to tackle the measure that would repeal key parts of the Obamacare law as well as pursue other legislative priorities.