Bernie Sanders
Bernie SandersReuters

An AIPAC-backed letter to President Barack Obama urging a more “robust” defense package for Israel reportedly has garnered the signatures of 83 senators, including Republican presidential candidate Ted Cruz but not Democratic hopeful Bernie Sanders.

Reuters reported Monday that 51 Republicans and 32 Democrats, more than four-fifths of the Senate, had signed on to the document.

The letter, initiated by Sens. Lindsey Graham, R-S.C., and Chris Coons, D-Del., was one of the lobbying day requests during the American Israel Public Affairs Committee annual conference last month.

Reuters said Cruz, of Texas, had signed and Sanders, an Independent of Vermont, did not. Sanders is the first Jewish candidate to win major party nominating contests.

Israel and the United States are negotiating a 10-year defense assistance package, or Memorandum of Understanding, to follow the package set to expire next year that guarantees $3 billion annually. The new agreement is widely expected to be significantly larger.

AIPAC praised the letter.

"We applaud this statement from the Senate of overwhelming bipartisan support for a robust, new Memorandum of Understanding with Israel that increases aid while retaining the current terms of the existing program," the prominent Israel lobby's spokesman, Marshall Wittmann, said in a statement.

The letter does not specify an amount to increase the overall defense assistance package, but notes that Congress is already considering increasing the nearly $500 million annually it budgets for missile defense cooperation, which until now has been considered separately from the defense package.

It cites a series of what it depicts as enhanced threats in the region, including a missile buildup by Hezbollah in Lebanon; Syria becoming a battleground for an array of forces hostile to Israel, including Iran and militant Sunni Islamist groups, and an increase in terrorism in the Sinai.

The letter also notes what it says is the influx of weapons into the region and the possibility that Iran will abrogate the recent nuclear deal and seek nuclear weapons.

“The nature and breadth of the current threats mean that the United States must enhance its investment in the long-term security requirements of our closest Middle East ally,” the letter said. “We urge you to conclude an agreement for a robust MOU that increases aid while retaining the current terms of our existing aid program.”