Elon Musk's SpaceX reportedly is deepening its ties with US intelligence and military agencies with a secretive company satellite program called Starshield.

The Wall Street Journal reported Tuesday that SpaceX has won at least one major classified contract with the US government valued at $1.8 billion, in 2021, according to company documents that the Journal said it has seen.

The collaboration signals "a deepening connection'' between SpaceX, the leading company in the space industry, and the national security establishment, the Journal said.

A SpaceX spokesman didn't respond to requests for comment.

SpaceX said in the documents that funds from the contract were expected to become an important part of its future revenue for the company, according to the Journal.

Musk, who also leads the auto company Tesla, the social media company X and other ventures, founded SpaceX in 2002.

It operates the world's biggest fleet of satellites, about 5,400 as of mid-February. Those devices power Starlink, which is marketed for civilian use.

SpaceX's work for US defense clients has long included sending classified and military satellites into space.

Space X's Starshield unit works with government clients. Among its leaders is a retired US Air Force general, Terrence O'Shaughnessy, who joined SpaceX in 2020, according to the Journal.

Starshield won a $70 million contract from the military last August to provide communications to dozens of Pentagon partners.

The initial phase of the Starshield contract provides $15 million to SpaceX by Sept 30 for services that support 54 military "mission partners" across Defense Department branches.

The contract for Starshield follows one awarded in June by the Pentagon to buy an undefined number of Starlink ground terminals for use in Ukraine.

Musk and the Russian government last week denied reports by Ukraine's military intelligence agency that SpaceX was selling the broadband internet terminals to Russia for its troops fighting in Ukraine.

Starshield's online job postings have sought people with top-secret security clearances, as well as experience working with the Defense Department and intelligence community.

SpaceX has won national security clients for its satellite technologies — a different set of offerings from SpaceX's traditional work of blasting off satellites for those customers.

One such client has been the National Reconnaissance Office (NRO), according to people familiar with the matter, the Journal reported.

Based in an office park south of Dulles International Airport, the NRO draws staff from different Pentagon branches and the Central Intelligence Agency, who use satellite data to support national security and civilian agencies in the federal government. Its existence was a classified government secret until 1992.

It couldn't be determined what satellite technology from SpaceX the NRO has tapped, the Journal said.

An NRO spokesman told the Journal that the agency develops intelligence products with a range of partners. "We are deepening our relationships with other government agencies, the private sector, academia and other nations," the spokesman said.