Among 100 members of the U.S. Senate, 17 lawmakers—13 Democrats, three Republicans, and one independent—decided not to join the strong bipartisan support for a letter arguing that Israel should receive increased annual defense aid from America.

The letter, signed by 83 senators and addressed to President Barack Obama, cites a number of security threats facing Israel that justify “investment in the long-term security requirements” forAmerica’s “closest Middle East ally.” Israel is hoping that its U.S. defense package will rise from the current $3.1 billion per year to between $4 and $4.5 billion annually, while the Obama administration has proposed a target of $3.7 billion.

U.S. Sens. Chris Coons (D-Del.) and Lindsey Graham (R-S.C.) initiated the letter, which was not signed by the following 17 senators: Tammy Baldwin (D-Wis.), Barbara Boxer (D-Calif.), Sherrod Brown (D-Ohio), Tom Carper (D-Del.), Bob Corker (R-Tenn.), Al Franken (D-Minn.), Tim Kaine (D-Va.), Angus King (I-Maine), Patrick Leahy (D-Vt.), Chris Murphy (D-Conn.), Rand (R-Ky.), Jack Reed (D-R.I.), Bernie Sanders (D-Vt.), Jeff Sessions (R-Ala.), Jeanne Shaheen (D-N.H.), John Tester (D-Mont.), and Tom Udall (D-N.M.)