SoftBank this month reported a record loss at its Vision Fund unit as tech valuations slid, with founder and Chief Executive Masayoshi Son promising to rein in investing activity and preserve cash.

In an effort to raise cash, SoftBank hopes to list chip designer Arm after a deal to sell the business to Nvidia fell apart after hitting regulatory hurdles.

Moody's said the deal's collapse "showcases the challenges around quickly realizing full value for such stakes" and added that SoftBank's attempt to list Arm "faces execution risk in the timing and valuation".

SoftBank asked Moody's to withdraw its ratings in 2020. The conglomerate said the latest assessment "is based on their subjective assumptions and hypotheses with no reasonable basis for support".

The company has emphasised its financial leeway, saying that its loan-to-value ratio was 20.4% at March-end, an improvement on three months earlier.

Moody's said that, unlike SoftBank, it includes an $8 billion loan secured against the Arm stake in its measure of the group's leverage.

"It is unclear whether (SoftBank) will sustainably reduce its leverage," Moody's said.

(Reporting by Sam Nussey; editing by Jason Neely)

By Sam Nussey