Sudan said Sunday that remnants of a missile used in a mysterious attack that killed two people on April 5 proved that Israel carried out the strike.
Israel has declined to comment on the incident, which mirrored a similar attack on Sudan's east in 2009 for which it neither admitted nor denied responsibility.
A car carrying two Sudanese nationals was targeted near Port Sudan's airport.
"The definitive proof that Israel was behind this attack is that the rockets used by the American-made Apache helicopters are only owned by Israel in the region," the Foreign Ministry statement said.
It said remnants at the scene showed the weapon was an AGM-114 Hellfire air-to-surface missile.
The aircraft, the ministry said, had flown in from the direction of the Red Sea, scrambling Sudanese radar systems and following Port Sudan airport flight paths.
East Sudan has long been a route for the smuggling of arms that often pass through Egypt's Sinai desert and reach the Gaza Strip, territory controlled by Hamas Islamists, via tunnels under the border.
According to the website of the Stockholm International Peace Research Institute (SIPRI), which monitors arms transfers worldwide, the United States delivered 250 Hellfire missiles to Israel in 1998-1999 and 680 in 2005-2006.
The only other country in the region listed by SIPRI as having Hellfires -- which are also used by U.S. forces -- is the United Arab Emirates, which bought 289 of the missiles in 2005.
Sudan said Israel, which it considers an enemy state, was trying to derail efforts to normalize ties with Washington. The United States started the process of removing Sudan from its list of state sponsors of terror after Khartoum recognized a vote by its south to secede in July.
Sudan has close ties with Hamas, but denies it offers direct support to the group. Washington designates Hamas a terrorist organization, citing its refusal to recognize Israel, renounce violence and accept existing Israeli-Palestinian interim peace deals.
Khartoum says it has begun the process of lodging a formal complaint against Israel at the U.N. Security Council.