US President Donald Trump said he will sign a $738bn defence policy bill on Friday that includes paid parental leave, the creation of a space force and a measure providing another means to punish Syrian President Bashar al-Assad and his allies with sanctions.

“I will be signing our 738 Billion Dollar Defense Spending Bill today,” Trump tweeted on Friday “It will include 12 weeks Paid Parental Leave, gives our troops a raise, importantly creates the SPACE FORCE, SOUTHERN BORDER WALL FUNDING, repeals “Cadillac Tax” on Health Plans, raises smoking age to 21! BIG!”

The Republican-controlled Senate on Tuesday voted 86 to eight in favour of the National Defense Authorization Act, or NDAA. The Democratic-led House approved the bill by 377-48 last week.

Because it is one of the few pieces of major legislation Congress passes every year, the NDAA becomes a vehicle for a range of policy measures as well as setting everything from military pay levels to which ships or aircraft will be modernised, purchased or discontinued.

Its passage came amid sharp partisan divisions over the impeachment of Trump over his dealings in Ukraine.

Paid parental leave, border wall, Space Force

The legislation included a 3.1 percent pay increase for the troops; the first-ever paid family leave for all federal workers; and the creation of a Space Force, the first new branch of the US military in more than 60 years and a top military priority for Trump.

Trump has crowed about the “US Space Force” provision, which mostly reorganises existing personnel into a new branch of the Air Force. The House had passed the idea in previous years under Republican control only to see it die in the Senate.

The Democratic-led House and Republican-led Senate each voted for a version of the NDAA earlier this year. Then negotiators from both parties and both houses of Congress, and representatives from the White House, worked for months to reach the compromise version of the bill passed by the House last week and the Senate on Tuesday.

Democrats were forced to drop a provision to block Trump from transferring money from Pentagon accounts to construct a fence along the US-Mexico border. They also dropped protections for transgender troops and tougher regulations on toxic chemicals that are found in firefighting foam used at military installations.

Negotiations broke free, however, after Republicans agreed to accept a Democratic demand – endorsed by Trump in end-stage negotiations – for the landmark parental leave provision, which provides 12 weeks of paid parental leave to federal employees.

Syria, Russia, Iran

Democrats also let go of House-passed provisions to restrict Trump from waging war against Iran unless Congress approves; ban deployment of new submarine-launched, low-yield nuclear weapons; and ban US military assistance for attacks by Saudi-led forces in Yemen.

The bill contains a measure called the Caesar Act, which had failed to gain congressional approval in several previous attempts. It applies sanctions to supporters of Syrian President Bashar al-Assad‘s military efforts in the country’s civil war, which include Russia and Iran. It also grants authorities to the US secretary of state to support those collecting evidence and pursuing prosecutions of people who have committed war crimes in Syria.

A Syrian man comforts another on the rubble of a building after a reported Russian air raid on a popular market in the village of Balyun in Syria’s northwestern Idlib province [File: Omar Haj Kadour/AFP]

The popularity of the annual defence policy bill reflects strong support among members of Congress for military personnel and the economic boost that military installations and defence contractors provide back home. Recent defence increases have been a boon for contractors such as Lockheed Martin, lead manufacturer of the F-35 fighter.

Despite broad bipartisan support, a few left-leaning Democrats and libertarian-leaning Republicans voted against the NDAA because it did not include policy planks that would have restrained Trump’s war powers, including the ban on support for Saudi Arabia’s air campaign in Yemen.

Some also objected to the 2.8 percent increase in military spending, as the national debt is skyrocketing.