Barack Obama vetoes 9/11 lawsuit bill

US President Barack Obama has vetoed a bill that will allow family members of 9/11 victims to sue Saudi Arabia, pitting him against Congress and both presidential candidates on an emotionally charged matter.

The White House claimed the legislation could expose US diplomats and servicemen to litigation in other countries. Republican and Democratic leaders in Congress say they'll override Obama's veto next week, CNN reported on Friday.

Obama has now issued 12 vetoes. If successful, Congress' override would be the first of Obama's presidency.

Support for the "Justice Against Sponsors of Terrorism Act" ran high among lawmakers, who overwhelmingly passed the bill earlier this year after pressure from victims' groups.

The bill would end foreign countries' immunity in the US from lawsuits, allowing federal civil suits to go forward if the country is determined to have had a hand in a US terror attack.

In his veto message, Obama wrote he had "deep sympathy for the families of the victims of the terrorist attacks of September 11, 2001, who have suffered grievously."

But he maintained the legislation would seriously hurt US national security interests and cause harm to important alliances, saying it "would neither protect Americans from terrorist attacks nor improve the effectiveness of our response to such attacks."

He warned that the law would hurt the effectiveness of the administration's action against terrorism by taking questions of foreign states' involvement in terrorism "out of the hands of national security and foreign policy professionals and placing them in the hands of private litigants and courts."

Obama also said the move would open Americans abroad, especially those serving in the military, to prosecutions by foreign countries, since this would remove the reciprocal agreements that now protect both sides from such lawsuits.

He also pointed to complaints that allied nations have made about the measure. This legislation, he said, "threatens to limit their cooperation on key national security issues, including counter terrorism initiatives, at a crucial time when we are trying to build coalitions, not create divisions."

Demonstrating the difficult political position the White House is in, Democratic presidential nominee Hillary Clinton, Obama's former secretary of state, expressed her support for the legislation Friday.

"Clinton continues to support the efforts by Sen. (Chuck) Schumer and his colleagues in Congress to secure the ability of 9/11 families and other victims of terror to hold accountable those responsible," said Jesse Lehrich, a Clinton spokesman. "She would sign this legislation if it came to her desk."

Following the veto, Republican presidential contender Donald Trump said in a statement the move "is shameful and will go down as one of the low points of his presidency." Trump, too, said he would sign the legislation as president.

Schumer, a New York Democrat who was a lead supporter of the bill, called the veto "a disappointing decision that will be swiftly and soundly overturned in Congress."