President Donald Trump on Monday prodded the Republican-led U.S. Congress to pass major health care legislation but huge obstacles remained, with a senior lawmaker saying the Senate was unlikely to take up the stalled bill until next week.

The House of Representatives approved its health care bill in May but the Senate¡¯s version appeared to be in growing trouble as lawmakers returned to Washington from a week-long recess.

¡°I cannot imagine that Congress would dare to leave Washington without a beautiful new HealthCare bill fully approved and ready to go!¡± Trump wrote on Twitter, referring to the seven-year Republican quest to dismantle Democratic former President Barack Obama¡¯s signature legislative achievement.