WASHINGTON, July 18 (Reuters) - After Republicans' effort to pass a healthcare bill in the Senate collapsed on Monday, U.S. President Donald Trump on Tuesday put the blame on Democrats and a few members of his own party, but vowed to come back with "a great healthcare plan."

"We were let down by all of the Democrats and a few Republicans. Most Republicans were loyal, terrific & worked really hard. We will return!" Trump wrote on Twitter.

"As I have always said, let ObamaCare fail and then come together and do a great healthcare plan. Stay tuned!" Trump added. (Reporting by Susan Heavey)