US Senate Republicans on Tuesday found themselves forced - due to internal divisions - to postpone a vote on the controversial bill designed to replace former President Barack Obama's healthcare reform, a bill that could leave more than 20 million Americans without medical coverage.

Senate Majority Leader Mitch McConnell had to delay the date for the vote on the measure until after the July 4 recess.

"We're going to continue the discussions within our conference on the differences that we have that we're going to try to litigate," McConnell told reporters after informing his GOP colleagues about the delay.

"We're still working on trying to get to at least 50 people in a comfortable place" to support the bill in a Senate vote, he said, referring to the fact that the GOP needs at least 50 senators to vote for the bill to ensure its passage.

President Donald Trump has promised to repeal and replace ObamaCare, which was implemented in 2010 and constitutes his predecessor's signature piece of legislation.

The Senate GOP leader said that Trump is very involved in the negotiations to get conservative Republican senators to fall into line and agree to support the new healthcare bill.

On Monday, the Congressional Budget Office, an independent agency that provides data and analysis for Congress, declared that 22 million people would lose their medical coverage before 2026 under the plan.

Trump wants the Senate version of the bill to get to his desk as soon as possible so that he can sign it, thus cutting funds to Medicaid, allowing people with preexisting conditions to be denied guaranteed coverage and penalizing people without insurance by making them wait six months to repurchase for coverage.

ObamaCare forces people to buy private health insurance by levying fines on those who do not do so, a move designed to increase the number of people covered and thus lower individual premium costs, as well as increasing coverage for the poor, people under age 26 and those with preexisting conditions.

McConnell, who had hoped to be able to start Senate debate on the bill this week, now must scramble to get enough support to bring the measure to a successful vote.

Democrats on Tuesday once again called the plan a tax cut for people making more than $875,000 per year.

Senate Minority Leader Chuck Schumer, meanwhile, said that "This Republican bill is rotten to the core," insinuating that McConnell intends to "cut back-room deals" and resort to using a slushfund to "buy off" heretofore unsupportive senators.