A human rights group has determined that the Syrian government deliberately diverted international aid in order to starve besieged populations, ABC News reported Tuesday.

In its new report Access Denied, Physicians for Human Rights accused the Iran-backed regime of President Bashar al-Assad from blocking United Nations access to needy Syrian civilians and reneging on an agreement to allow aid convoys to reach besieged populations. Those convoys that did reach their final destination did not carry sufficient supplies to alleviate the shortages in the affected areas, the group charged.

“[By] willfully impeding aid in an attempt to starve civilians, and collectively punishing entire communities through besiegement, the Syrian government is guilty of war crimes,” it said.

Elise Baker, research coordinator at Physicians for Human Rights and author of the report, told ABC News that that the “vast majority of convoys that did not actually reach populations in need were denied access because of restrictions from Syrian government officials.”

“What surprised us the most is how clearly deliberate all of these restrictions in the aid delivery process are,” she added.

“The U.N. should say, ‘We are delivering aid based on humanitarian principles rather than your restrictions and manipulations’ — and report on it publicly when a convoy is turned away,” Baker recommended. “Right now the aid delivery process allows the Syrian government to appear collaborative when actually it’s blocking aid.”

The report was based on data reported monthly by the UN secretary general to the Security Council.

The Assad regime’s interference in the delivery of aid prompted 73 aid groups to stop cooperating with the UN last September, citing “manipulation” by the Syrian government.

[Photo: MSNBC / YouTube ]