WASHINGTON (AP) — Nine senior Senate Democrats and independent Sen. Bernie Sanders urged the Biden administration Friday to withhold part of the United States’ annual military aid to Egypt for a third consecutive year, calling it important to keep up the pressure on President Abdel-Fattah el-Sissi on human rights abuses.

More than 20 leading U.S. and international rights groups and think tanks separately made the same appeal, arguing that the U.S. practice of holding back some aid was leading el-Sissi to make “limited, albeit insufficient ” rights improvements in Egypt.

About a quarter of a $1.3 billion appropriation is at issue.

The request may be especially tough this year for President Joe Biden, who is focusing on keeping countries around the world, including Egypt, aligned behind Ukraine as it battles Russia’s globally destabilizing invasion. Neither the State Department nor the Egyptian Embassy in Washington immediately responded to requests for comment Friday.

The letters, addressed to Secretary of State Antony Blinken, serve as an opening round in Democratic lawmakers’ annual battle to trim aid funding as a way to pressure el-Sissi’s government to curb rights abuses.

The State Department’s annual human rights report has repeatedly faulted Egypt, even as an important strategic ally in the region, for extrajudicial killings and torture, detention of thousands of writers, reporters, advocates and other political prisoners, suppression of news media and other abuses.

The Washington Post, citing secret U.S. documents leaked online by a Massachusetts Air National Guard member, reported in April that U.S. officials had talked Egypt out of secretly providing rockets to Russia. Egypt agreed instead to provide the United States with artillery rounds for transfer for Ukraine, the Post reported, citing another leaked document.

Congress in recent years has made the U.S. payment of roughly $300 million of U.S. military aid contingent on Egypt’s government showing progress on rights, although the State Department can partially override that, on national security grounds.

While shared U.S.-Egyptian security objectives make it important for the U.S. to continue supporting Egypt’s military in general, the senators argued, “we can continue to support these objectives while enforcing the law to withhold $320 million in military aid to Egypt due to a lack of necessary progress on human rights.”

Sen. Chris Murphy of Connecticut led the letter. Richard Blumenthal, also of Connecticut, Sherrod Brown of Ohio, Richard Durbin of Illinois, Bernie Sanders of Vermont, Chris Van Hollen and Ben Cardin of Maryland, Jeff Merkley of Oregon, Elizabeth Warren of Massachusetts, Tim Kaine of Virginia and Tom Carper of Delaware also signed.

“As the administration’s decision to withhold a portion of Egypt’s $1.3 billion appropriation for each of the last two years demonstrates, the bilateral security relationship can be effectively sustained at a reduced level of assistance while upholding our values,” the senators wrote.

The administration is expected to make a decision on the matter next month, although the legal deadline is Sept. 30.

Egypt’s jailing and silencing of critics have drawn international condemnation and are points of friction between the North African country and the West. That includes the United States, the Egyptian military’s most generous supporter.

Amnesty International, Human Rights Watch, PEN International and other rights groups and think tanks in the other letter Friday credited the Biden administration’s financial pressure with helping persuade Egypt to free more than 1,000 political detainees. At the same time, rights advocates say, Egypt has detained nearly 5,000 others, and renewed pretrial detentions of thousands more.