Story highlights President Barack Obama had vetoed the bill

It initially won overwhelming support in Congress

Washington (CNN) The Senate will vote Wednesday to override President Barack Obama's veto of a bill to give victims and families of the 9/11 terrorist attacks the legal right to sue Saudi Arabia for any purported role in the plot, Senate Majority Leader Mitch McConnell said Monday.

The measure will need a two-thirds vote of the chamber to succeed -- which is expected -- before going to the House for a similar override vote later this week.

It would be the first time in Obama's nearly eight years in office that one of his vetoes will be overturned.

The President opposes the bill because he says it could open the door to lawsuits against the US for actions taken by military service members, diplomats and others.

Obama expressed sympathy for the 9/11 families in his veto message Friday, but said he vetoed the bill because 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."

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