The Pentagon has said that Egypt did not inform it in advance of its intention to conduct airstrikes against Islamic State bases in Libya earlier this week.
“We weren't notified ahead of time," spokesman Rear Admiral John Kirby told a Pentagon briefing on Wednesday. "We didn't participate or support them in any way, and we're not taking a position on it.”
Egypt's jets on Monday bombed Islamic State group arm caches and training camps in the eastern Libyan city of Derna after the Al-Qaeda offshoot released a video showing the beheading of 20 Egyptian Coptic Christians working in the North African country.
The United States said earlier that it respected Egypt's right to defend itself, following its intervention in Libya, which was coordinated with the Libyan army.
Describing ties with Egypt as "complex," Kirby stressed that Cairo, to which Washington provides $1.5 billion in annual aid, is a strategic regional partner.
"That hasn't changed," he said, emphasising common interests Washington shares with its longtime Middle Eastern ally with respect to "terrorism, regional stability and including peace with Israel."
The US withheld part of its military aid to Cairo late in 2013, on the condition that it carried through democratic reforms, after the overthrow of Islamist president Mohamed Morsi and an ensuing crackdown on his supporters.
The partial suspension was relaxed with Egypt receiving 10 Apache attack helicopters in November 2014 to help with its counter-terrorism efforts in the Sinai Peninsula.
But the Pentagon press secretary said that Washington continues to hold back the delivery of larger weaponry items, including F-16 fighter jets, M1A1 tanks, and harpoon missiles in line with political developments in the Arab world's most populous state.
"Those are still on hold, and there's been no decision with respect to that," he said.