Families of the Americans killed in a truck bombing at the U.S. Embassy in Kenya will go to Arlington National Cemetery on Friday to visit the gravesites of their loved ones, as they have for 22 years, on every anniversary of the attack.

This year will be different, though. The State Department has negotiated a settlement in which Sudan would pay $335 million to compensate the victims and their survivors — Americans and foreign nationals — for the twin 1998 bombings by al-Qaeda operatives at the U.S. embassies in Nairobi and Dar es Salaam, Tanzania. In return, Sudan would be dropped from the list of state sponsors of terrorism carrying the harshest of U.S. sanctions.

A group of American families and survivors is urging Congress to ratify the agreement, despite concerns over differing sums offered to U.S. citizens and Africans, including some who later became U.S. citizens, and over the potential effect of the agreement on lawsuits against Sudan filed in U.S. courts.

Their sense of urgency is driven not only by disappointment over delayed accountability but also by the belief that the opportunity for settling the cases may be closing.

Sudan’s responsibility stems from the safe harbor offered Osama bin Laden by Omar Hassan al-Bashir, Sudan’s authoritarian leader who was ousted by pro-democracy protesters last year. Sudan has been designated a state sponsor of terrorism since 1993, though U.S. officials in Khartoum have said in recent years that the government has cooperated in the fight against terrorism.

Now, Sudan’s transitional government is in danger of collapse amid economic and political instability, widespread poverty and hunger, and the coronavirus pandemic. An assassination attempt was made in March against Prime Minister Abdalla Hamdok.

Supporters of the agreement say that only the economic boost of being dropped from the terrorism list can rescue the transitional government.

“By continuing to call them a state sponsor of terrorism, we in the United States are increasing the likelihood of the collapse of that government, the replacement of that government with an authoritarian system, which will return Sudan to instability and massacres across the country,” said Edward R. Royce, a former chairman of the House Foreign Affairs Committee who has thrown his support behind the settlement.

Secretary of State Mike Pompeo has the authority to simply approve the compensation for U.S. citizens and drop Sudan from the terrorism list. But he cannot negotiate compensation for the foreign nationals employed by the embassies, even if they have since become naturalized U.S. citizens.

The two blasts killed 224 people, including 12 Americans who all were killed at the embassy in Nairobi, situated at a busy street corner in the center of the city.

Sudan offered to pay $335 million in compensation, including $100 million for the foreign nationals. That works out to at least $3 million for the Americans, but just $400,000 for the noncitizens. Many of them have sued Sudan in U.S. courts, where they theoretically could be awarded more. But Sudan has no assets in the United States, and there is no guarantee they could collect.

The inequitable compensation, and concerns about the effect dropping Sudan from the terrorism list could have on lawsuits, has delayed the introduction of a draft bill in the Senate.

Sen. Robert Menendez (N.J.), the ranking Democrat on the Senate Foreign Relations Committee, said he was seeking a fair resolution of the claims against Sudan. But he said the settlement proposed by the Trump administration is “deeply flawed.”

“It favors some American citizens over others,” he said in a statement emailed to The Washington Post, and added, “We need a deal that, at minimum, is fair to all Americans with claims. There is no serious effort in the Senate to approve the Trump deal because it doesn’t meet that minimum standard.”

“Let’s not let perfect be the enemy of the good,” said Riz Khaliq, a former commercial officer at the embassy in Nairobi who was injured during the blast. “Every agreement could be better. Let’s have a look at what’s attainable. It’s a ticking time bomb Sudan’s government is in if it doesn’t get supported.”

Edith Bartley, a spokeswoman for the families of Americans killed in Nairobi whose father and brother were killed in the bombing, said U.S. national security interests could be compromised if the agreement is not endorsed and Sudan falls into chaos.

“It can mean the difference between more U.S. bodies coming home or not,” she said. “It can mean the difference between more U.S. installations being attacked.”

Democratic senators issued a statement Thursday calling on the White House and Congress “to deliver justice to the victims and their families and appropriately and equitably address terrorism-related claims against Sudan.”

The 1998 attacks continue to cast a long shadow over both embassies. In Dar es Salaam, a memorial titled “Hope out of Sorrow” was erected two years ago on the embassy grounds. In Nairobi, visiting secretaries of state always lay a wreath Aug. 7 at Memorial Park at the embassy.