WASHINGTON - US Congress Wednesday unveiled a bipartisan spending package worth 1.3 trillion US dollars that would keep government agencies operating through September.

The measure, coming after congressional leaders met earlier in the day, will prevent the third government shutdown this year if it is passed and signed into law by the Friday-night deadline.

The bill allows big spending increases for defense and domestic programs, while adding money for infrastructure projects, veterans and measures to combat the opioid crisis.

A bipartisan Senate bill, aimed at improving state compliance with the national background check system for firearm purchases, is also wrapped into the spending package, along with gun-related provisions.

House Speaker Paul Ryan, Congress's top Republican, said the bill marks "the beginning of a new era" for the US military, while Senate Minority Leader Chuck Schumer said "Democrats feel very good" about it.

Though the White House said the plan has President Donald Trump's support, the package gives him only about 1.6 billion dollars for construction of a border wall with Mexico and other border security measures, far short of the 25 billion dollars in long-term funding that the administration has sought.

Besides, the bill does not contain steps to protect so-called Dreamers from deportation.

Dreamers are recipients of the Deferred Action for Childhood Arrivals, a program that the Obama administration created in 2012 to defer deportation for people who came to the United States illegally as children but was terminated by Trump last fall.

The time for the vote is tight. If the house passes the bill Thursday, the Senate could take it up later that day, which means passage would probably not take place until Friday at the earliest.

Also, it is not known if anyone in the Senate will use procedural hurdles that could slow down the bill's passage and force another technical government shutdown.