The budget plan, which the administration will unveil as the president travels abroad, will reportedly seek funds for the creation of a program to give new parents six weeks of paid leave following the birth or adoption of a child, the Post reports, citing two senior White House budget office officials. The United States is the only developed nation in the world that guarantees new parents zero paid time off following the arrival of a baby.

Officials told the Washington Post that the paid leave program is expected to cost about $25 billion a year and benefit some 1.3 million people. The details of the program still need hammering out in Congress, and Ivanka Trump is expected to play a key role in that process.

A spokesperson for the Office of Management and Budget confirmed the reports to Fortune on Friday and said further details will be available when the budget is released on Tuesday.

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Paid leave’s inclusion in the budget will make good on a campaign promise of President Trump, who, as a candidate in September, introduced a plan to guarantee six weeks of paid maternity leave. That initial proposal drew criticism for only covering birth mothers—not fathers or adoptive parents. Since then, the administration has broadened its approach to paid leave to include dads and parents who choose to adopt.

The proposal to be unveiled next week will put the onus on states to create their own programs. Only three states—New Jersey, Rhode Island, and California—already have such programs in place. New York and Washington, D.C. have approved plans to roll out their own programs next year. An administration official told the AP that this approach provides states with flexibility in setting up their programs. But the tactic also puts the burden on states to fund the program and could mean benefits will vary by location.

In advocating for paid maternity leave, Trump is breaking from the traditional stance of the Republican party in a radical way. The GOP has long held that requiring employers to guarantee paid time off for new moms or promising it through a government program is in conflict with the party’s insistence on limiting Washington’s reach, so it’s unclear what level of support Trump’s latest proposal will receive from Republicans on the hill.

Democrats have long championed a federal paid leave policy, but they could push back against the limited scope of Trump’s plan.

In February, Sen. Kirsten Gillibrand (D-N.Y.) and Rep. Rosa DeLauro (D-Conn.) reintroduced a bill for paid family leave that guarantees two-thirds pay for up to 12 weeks to workers who take time off for their own health conditions—including pregnancy and childbirth—or to care for others.

Trump’s six-week proposal would be an improvement over the U.S.’s current policy that gives new parents no paid time off—mothers can take up to 12 weeks of unpaid leave—but his plan doesn’t do much to move the needle on providing new moms with more support compared to maternity leave policies abroad. When measured against the lengths of policies in other OECD countries, his proposed six weeks paid leave would move the United States from dead last to tied for last place with Portugal and Australia.

This story has been updated to reflect a response from the OMB.