House Speaker Emerita Nancy Pelosi (D-Calif.) has split with President Joe Biden by joining progressives in their calls to halt both current and future U.S. weapons transfers to Israel.

Forty members of Congress signed a letter to Biden, dated Friday, stating that the deadly attack on World Central Kitchen aid workers necessitates investigation into whether Israel is using U.S. weaponry in compliance with U.S. and international law.

Pelosis support, though, is particularly significant given her long working relationship with Biden.

Seven aid workers who had coordinated their movements with the Israeli military and traveled in clearly marked vehicles were struck Monday and killed , stirring further global outrage over Israels handling of the war.

One of the workers was an American citizen. All were working to feed Palestinians in the Gaza Strip as it faces famine.

The day of the World Central Kitchen attack, the Biden administration reportedly approved an arms shipment that included hundreds of 2,000-pound bombs and other, smaller bombs. A sale of up to 50 F-15 fighter jets is also reportedly pending .

We strongly urge you to reconsider your recent decision to authorize the transfer of a new arms package to Israel, and to withhold this and any future offensive arms transfers until a full investigation into the airstrike is completed, read the letter to Biden and U.S. Secretary of State Antony Blinken.

If this strike is found to have violated U.S. or international law, we urge you to continue withholding these transfers until those responsible are held accountable, it continued. We also urge you to withhold these transfers if Israel fails to sufficiently mitigate harm to innocent civilians in Gaza, including aid workers, and if it fails to facilitate or arbitrarily denies or restricts the transport and delivery of humanitarian aid into Gaza.

Other signees included Reps. Jamaal Bowman (D-N.Y.), Cori Bush (D-Mo.) Debbie Dingell (D-Mich.), Barbara Lee (D-Calif.), Alexandria Ocasio-Cortez (D-N.Y.), Ilhan Omar (D-Minn.) and Rashida Tlaib (D-Mich.).

Biden has voiced strong support for Israel since Hamas-led militants killed more than 1,100 people in their Oct. 7 attack on the country sparking large protest votes in some states Democratic primaries.

His tone, however, shifted this week during a discussion with Israeli Prime Minister Benjamin Netanyahu . Biden called for an immediate cease-fire and told Netanyahu that future U.S. support will depend on what Israel does to protect civilians and aid workers in the Gaza Strip. The current situation was unacceptable, Biden said.

Hours after the discussion, Israel announced that it would be opening two humanitarian aid routes into Gaza.

The Israeli military also said Friday that it had dismissed two officers and reprimanded three others in connection with the World Central Kitchen attack.

House Republicans have scheduled a vote next week on a resolution criticizing Bidens policy shift as one-sided .