The departures of UK investment minister Gerry Grimstone and digital minister Chris Philp after the collapse of the government this month have led SoftBank to pause talks about Arm's IPO in London next year, the FT reported.
Instead, the company will continue to pursue a share offering for the business in New York.
SoftBank founder Masayoshi Son has repeatedly said his primary focus is to take Arm public in the US because of its deep investor base and attractive valuations.
In June, Mr Son said he would also consider a London listing, in part because of political appeal.
Both UK ministers who resigned played leading roles in talks with the Japanese tech investor, the FT reported.
A listing in Arm’s home market could still happen, but SoftBank remains focused on the US in 2023, sources said.
SoftBank did not immediately return requests for comment.
The Financial Times reported earlier that SoftBank had stopped work on a London IPO.
Arm, which the Japanese company acquired in 2016, is based in Cambridge, England.
It was one of the UK’s most important technology companies before the purchase and still has the majority of its operations there.
Mr Johnson’s administration had lobbied hard to bring at least part of any initial public offering to the UK’s capital market.
Arm sells and licenses technology that is used by semiconductors in everything from smartphones to supercomputers.
The pervasiveness of its products has made its planned IPO a closely watched event in the $550 billion chip industry.
Mr Son has said he plans to sell a portion of Arm before the end of the company’s financial year next March.
The prospect for a return on his $32bn purchase of Arm have dimmed as investors have shied away from chip-related stocks.
The benchmark Philadelphia Stock Exchange Semiconductor Index has lost almost a third of its value in 2022.