WASHINGTON (Reuters) - U.S. Senate leaders from both parties on Wednesday reached a deal to raise government spending and take other steps meant to curb Capitol Hill budget squabbling.

FILE PHOTO: The U.S. Capitol building is lit at dusk in Washington, U.S., December 18, 2017. REUTERS/Joshua Roberts/Files

The complex agreement, backed by House of Representatives Speaker Paul Ryan, could face resistance among conservative House Republicans concerned about the deficit impact.

High-stakes votes in both chambers were expected on Thursday, when a deadline will arrive for Congress to approve a stopgap spending bill to avert a government shutdown. The deal also includes another stopgap measure to buy time for budget writers to flesh out the details of the two-year spending deal.

Here is what is in the deal, according to Senate leaders:

RAISES SPENDING LEVELS

The deal would increase government spending by nearly $300 billion over two years. It would increase discretionary defense spending by $165 billion over current spending caps. It would increase non-defense domestic discretionary spending caps by $131 billion over current spending levels.

NON-DEFENSE SPENDING

The $131 billion increase in non-defense spending would include $20 billion for infrastructure spending and $6 billion to fund the fight against opioids and mental health crises.

CHILDREN’S HEALTH INSURANCE PROGRAM

The deal would extend funding for the Children’s Health Insurance Program (CHIP) for 10 years instead of the current six.

DEBT CEILING

The deal includes an extension of the government’s debt ceiling to March 2019. The Treasury Department has warned that without an extension in borrowing authority by Congress, the government would run out of borrowing options in the first half of next month, risking default.

TEMPORARY FUNDING MEASURE

The deal would avert a government shutdown on Thursday when the current government funding measure expires by including a short-term measure to fund the government at current levels through March 23 while appropriators write a detailed budget bill.

DISASTER ASSISTANCE

A disaster aid package of $90 billion for U.S. areas affected by events such as Hurricanes Irma, Harvey and Maria, as well as the California wildfires, will also be included.

IMMIGRATION

Immigration legislation is not included in the deal reached by Senate leaders. Senate Majority Leader Mitch McConnell has said the Senate will begin debating immigration legislation next week. House Democratic leader Nancy Pelosi delivered a marathon, eight-hour speech about young “Dreamer” immigrants on the House floor on Wednesday in an attempt to extract the same promise from Ryan.