SpaceX CEO Elon Musk said on Thursday the IPO-bound company had only agreed to lease its Colossus AI training data center clusters to Anthropic for six months, though he added it was "possible" the arrangement could extend for multiple years.

"SpaceX has not committed to leasing Colossus for years, although it's possible that may be what happens," Musk said in a post on X.

Earlier this year, SpaceX inked deals for Anthropic to pay it $1.25 billion a month to use compute capacity from its Colossus and Colossus II data center clusters in Memphis, Tennessee through May 2029.

SpaceX, which filed for IPO last week, said in the regulatory filing that both companies could terminate the agreements with a 90-day notice. The filing did not make any mention of the six-month lease.

SpaceX and Anthropic did not immediately respond to a Reuters request for comment outside regular business hours.

The agreement is a 180-day lease with a mutual 90-day cancellation notice thereafter, Musk said.

"The short term was our request, not Anthropic's," he said on X, referring to the Colossus deal.

"We won't leave them hanging and will provide a reasonable off-ramp, but if compute gets super tight I said we might need it back at some point," the billionaire added.

Last week, Musk posted on X that SpaceX was in discussions with other companies about "offering AI compute as a service at significant scale."

SpaceX's AI segment lost about $2.5 billion from operations in the March quarter, on segment revenue of $818 million, according to its IPO filing.