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THE HAGUE/WASHINGTON, May 8 (Reuters) - The United

States has suspended a shipment of weapons to Israel, including

heavy bombs the U.S. ally used in its campaign against Hamas

militants in Gaza which has killed more than 34,000

Palestinians.

The suspension comes as Israeli Prime Minister Benjamin

Netanyahu continues a military assault on the Palestinian city

of Rafah, over the objections of U.S. President Joe Biden.

Here's what we know so far:

WHAT BOMBS WERE BLOCKED?

Washington paused one shipment consisting of 1,800

2,000-pound (907-kg) bombs and 1,700 500-pound bombs, according

to U.S. officials.

Four sources said the shipments, which have been delayed for

at least two weeks, involved Boeing ( BA )-made Joint Direct Attack

Munitions, which convert dumb bombs into precision-guided ones,

as well as Small Diameter Bombs (SDB-1). The SDB-1 is a

precision guided glide bomb that packs 250 pounds of explosive.

They were part of an earlier approved shipment to Israel, not

the recent $95 billion supplemental aid package the U.S.

Congress passed in April.

WHY IS THE U.S. BLOCKING THESE BOMBS?

The U.S. is reviewing "near term security assistance,"

Defense Secretary Lloyd Austin told a Senate hearing on

Wednesday "in the context of unfolding events in Rafah."

"We've been very clear...from the very beginning that Israel

shouldn't launch a major attack into Rafah without accounting

for and protecting the civilians that are in that battlespace,"

Austin said. More than one million Palestinian civilians have

sought shelter in Rafah, many previously displaced from other

parts of Gaza following Israel's orders to evacuate from there.

The U.S. decision was taken due to concerns about the

"end-use of the 2,000-pound bombs and the impact they could have

in dense urban settings as we have seen in other parts of Gaza,"

said a U.S. official speaking on condition of anonymity. The

U.S. had carefully reviewed the delivery of weapons that might

be used in Rafah, the official said.

WHEN WAS THE DECISION MADE? WAS BIDEN INVOLVED?

The decision was made last week, U.S. officials said. Biden

was directly involved. Biden confirmed the pause personally in a

CNN interview Wednesday.

"Civilians have been killed in Gaza as a consequence of

those bombs and other ways in which they go after population

centers," he said when asked about 2,000-pound bombs sent to

Israel.

WHAT KIND OF DAMAGE CAN 2,000-POUND BOMBS CAUSE?

Large bombs like 2,000-pound bombs have an impact over a wide

area. According to the United Nations, "The pressure from the

explosion can rupture lungs, burst sinus cavities and tear off

limbs hundreds of meters from the blast site."

The International Commission for the Red Cross in a 2022

reports the use of wide area explosives in a densely populated

area "is very likely to have indiscriminate effects or violate

the principle of proportionality."

WHAT WAS ISRAEL'S RESPONSE?

Israel denies targeting Palestinian civilians, saying its

sole interest is to annihilate Hamas and that it takes all

precautions to avoid unnecessary death.

After the news broke Tuesday in Washington, a senior Israeli

official declined to confirm the report. "If we have to fight

with our fingernails, then we'll do what we have to do," the

source said. A military spokesperson said any disagreements were

resolved in private.

WERE THESE BOMBS LEGAL FOR ISRAEL TO USE IN GAZA?

That is a matter of heated debate.

International humanitarian law does not explicitly ban

aerial bombing in densely populated areas, however civilians

cannot be targets and a specific military aim must be

proportionate to possible civilian casualties or damage.

WHAT DOES THE INTERNATIONAL CRIMINAL COURT SAY?

The statute of the International Criminal Court, which is

investigating the Israel-Gaza war, lists as a war crime

intentionally launching an attack when it is known that civilian

death or damage will be "clearly excessive" compared to any

direct military advantage.

HAS THE US WITHHELD MILITARY AID FROM ISRAEL BEFORE?

Yes, in 1982. President Ronald Reagan imposed a six-year ban

on cluster weapons sales to Israel after a Congressional

investigation found that Israel had used them in populated areas

during its 1982 invasion of Lebanon.

Israel's use of U.S.-made cluster bombs was reviewed under

President George W. Bush, over concerns they were used during a

2006 war with Hezbollah guerrillas in Lebanon.