WASHINGTON (AP) — Despite second thoughts, President Donald Trump swung behind a $1.3 trillion government spending bill Wednesday that would give him a partial victory on funding for a U.S.-Mexico border wall.

House Speaker Paul Ryan, R-Wis., rushed to the White House amid worries that Trump was talking about withdrawing his support for the measure, said a person familiar with White House communications with congressional leaders. However, after a face-to-face meeting, Trump confirmed his support.

"The president and the leaders discussed their support for the bill, which includes more funds to rebuild the military," said White House Press Secretary Sarah Sanders, adding that it would fund Trump priorities such as wall construction, add money to combat the opioid crisis and provide new infrastructure spending.

Earlier, a meeting of top congressional leaders produced tentative accords on two tax provisions and a decision to strengthen the criminal background check system for gun purchases. Ryan said an official agreement on the sweeping measure would likely come "very soon."

GOP aides said that Trump would win $1.6 billion for his promised wall and physical barriers along the border, which would include both new construction and the repair of existing segments. But he would be denied a more recent, far larger $25 billion request for multi-year funding for the wall project. Democrats said just $641 million would go to new segments of fencing and walls that double as levees.

Negotiators planned to unveil the massive government-wide spending bill later in the day in hopes of passing it before a Friday midnight deadline to avoid a government shutdown.

To the dismay of many Democrats, the measure won't renew protections for young "Dreamer" immigrants facing possible deportation. It also won't provide subsidies to insurers who cut costs for low-earning customers. And it won't have federal payments to insurance carriers to help them afford to cover their costliest clients.

The top four leaders of both House and Senate met Wednesday and emerged saying they basically had a deal.

"We're in a good place," Ryan said.

The bill would give Trump a huge budget increase for the military, while Democrats would cement wins on infrastructure and other domestic programs that they failed to get under President Barack Obama. The bill would fund a 2.4 percent pay raise for military personnel touted by Republicans.

Battles over budget priorities in the huge bill were all settled, while a handful of non-budget issues remained, including a GOP effort to fix a poorly drafted section of the recent tax cut law that is harming Midwestern grain companies.

At Wednesday's meeting, GOP aides said, top leaders including Ryan agreed to fix this so-called grain glitch — while adding a tax-credit provision sought by Democrats to boost low-income housing units.

They also said the agreement would add "Fix NICS" legislation designed to beef up compliance with gun background check reporting requirements.

Another fight would remove an earmark protecting money for a rail tunnel under the Hudson River that's a top priority of Trump's most powerful Democratic rival, Senate Minority Leader Chuck Schumer of New York. The project would remain eligible for funding, however, and a Schumer aide said it was likely to win well more than half of the $900 million sought for this year under rules governing various Department of Transportation accounts.

The measure on the table would provide major funding increases for the Pentagon — $80 billion over current limits — bringing the military budget to $700 billion and giving GOP defense hawks a long-sought victory.

"We made a promise to the country that we would rebuild our military. Aging equipment, personnel shortages, training lapses, maintenance lapses — all of this has cost us," said Ryan. "With this week's critical funding bill we will begin to reverse that damage."

Domestic accounts would get a generous 10 percent increase on average as well, awarding Democrats the sort of spending increases they sought but never secured during the Obama administration.

Both parties touted $4.6 billion in total funding to fight the nation's opioid addiction epidemic, a $3 billion increase. More than $2 billion would go to strengthen school safety through grants for training, security measures and treatment for the mentally ill. Medical research at the National Institutes of Health, a longstanding bipartisan priority, would receive a record $3 billion increase to $37 billion.

Community development block grants, which are flexible funds that are enormously popular with mayors and other local officials, would receive a huge $2.4 billion increase to $5.2 billion despite being marked for elimination in Trump's budget plan. And an Obama-era transportation grant program known as TIGER would see its budget tripled to $1.5 billion. Head Start for preschoolers would get a $610 million boost, while an additional $2.4 billion would go for child care grants.

Agencies historically unpopular with Republicans, such as the IRS, appear likely to get increases too, in part to prepare for implementation of the Republicans' recently passed tax measure. The Environmental Protection Agency, always a GOP target, would have its budget frozen at $8 billion.

Lawmakers agreed on the broad outlines of the budget plan last month. The legislation implementing that deal is viewed as possibly one of few bills moving through Congress this year, making it a target for lawmakers and lobbyists seeking to attach their top priorities.

And while Democrats yielded on $1.6 billion in wall funding, none of that money would go for the new prototypes that Trump recently visited in San Diego. Negotiators rejected Trump's plans to hire hundreds of new Border Patrol and immigration enforcement agents, congressional aides said.