Egyptian president Abdel Fatah El-Sisi told his military officials to keep this "under wraps".
Egypt planned to secretly produce and ship about 40,000 rockets to Russia to augment its depleted supply of ammunition during the ongoing Russia-Ukraine war, according to leaked US intelligence documents obtained by Washington Post. The outlet also said that Egyptian President Abdel Fattah El-Sisi held a meeting with his top military officials in which they discussed also providing artillery rounds and gunpowder to Russia. El-Sisi asked the officials to keep the entire plane under wraps "to avoid problem with the West".
The classified document is dated February 17, according to Washington Post.
The development has stunned American officials and politicians.
"If it's true that Sisi is covertly building rockets for Russia that could be used in Ukraine, we need to have a serious reckoning about the state of our relationship," junior senator from Connecticut Chris Murphy told the outlet.
Fox News said National Security Council spokesperson John Kirby has declined to confirm the validity of the documents, but warned that the material is not for public consumption.
It can impact America's relationship with Egypt, one of its closest allies in the Middle East and North Africa.
US Secretary of State Antony Blinken met with El-Sisi in late January in Cairo, after which the State Department issued a statement which said Mr Blinken "expressed the United States' solidarity with Egypt as it contends with the economic impact of Russia's brutal war in Ukraine."
US President Joe Biden also travelled to Egypt in November last year and met with El-Sisi. He had commended the Egyptian President for his country's stance on the war.
Egypt decided to help Russia to repay Moscow's "unspecified help earlier", according to an official named Mohamed Salah al-Din, the minister of state for military production.
The nature of that help is unclear. However, Egypt increased its reliance on Russian wheat last year amid disruptions to the global market stemming from Russia's war in Ukraine, according to news agency Reuters.