President Donald Trump took to Twitter on Sunday to make a big healthcare promise that is in contradiction to his administration's recent actions.

"I suggest that we add more dollars to Healthcare and make it the best anywhere," Trump tweeted. "ObamaCare is dead - the Republicans will do much better!"

But both the GOP healthcare bill supported by the president, as well as Trump's own budget, subtract from government healthcare expenditures. That has some healthcare experts concerned that the end result could leave many Americans with worse coverage than under the current system.

For instance, the Congressional Budget Office estimated that the American Health Care Act, the GOP's bill to repeal and replace Obamacare, would decrease federal expenditures on healthcare by just under $1 trillion between 2017 and 2026.

In fact, given the procedure Republicans are using to pass their healthcare bill, the only way to increase spending would be to add significant revenue-accumulating measures.

The GOP is using the budget reconciliation process to pass the AHCA, which means the bill can avoid a Democratic filibuster in the Senate. To use this process according to Senate rules, the bill must cut at least $1 billion from the federal deficit. The AHCA is designed to go through two committees, so it has to shave $2 billion off the deficit to be considered.

Separate from the AHCA, the Trump budget also proposes to slice a large amount of spending on healthcare from current levels.

Medicaid, the National Institutes of Health, Centers of Disease Control and Prevention, and many other healthcare-focused agencies would see their budgets significantly cut under the Trump proposal.