SoftBank is putting pressure on banks that are helping to finance Dish’s $25.5 billion rival takeover bid for Sprint, according to a Reuters report citing unnamed sources.

The Japanese firm, which owns 33 per cent of Chinese e-commerce giant Alibaba, has apparently warned banks funding Dish’s proposal that it could hurt their chances of being involved in Alibaba’s upcoming IPO.

At least one major bank, says the report, has now withdrawn from financing the Dish bid after SoftBank’s move.

Alibaba, which has yet to name a date for its listing, has not yet invited any banks to pitch their IPO services. The underwriters chosen, however, would likely get fat fees in one of the most eagerly-awaited IPOs since Facebook.

A source close to Alibaba, according to Reuters, said on 10 May that while SoftBank is a major investor, it does not make decisions for Alibaba’s management

Barclays, which is advising Dish, and Jefferies Group, are reportedly lined up to provide Dish financing. The US satellite TV player is believed to be speaking to more banks to join the financing. Jefferies and Barclays declined to comment.

Tension between SoftBank and Dish has risen in recent weeks. Masayoshi Son, SoftBank’s chairman, has disparaged Dish’s bid, calling it “incomplete and illusory”. He claims there are little synergies to be had between satellite and mobile.

And while the $25.5 billion Dish offer is higher than SoftBank’s – SoftBank struck a $20.1 billion takeover deal with Sprint management in October 2012 – Son claims that once its faster schedule and lower debt are taken into consideration, the SoftBank offer represents a 21 per cent premium to Dish’s counter proposal.

The SoftBank chief has further questioned whether Dish has got the ability to raise funds to finance its offer.

For its part, Dish boss Charlie Ergen claims SoftBank will now have to raise its offer to impress Sprint’s shareholders, while also arguing it would better for an American firm to take over Sprint than a foreign one.

Former Arkansas governor, Mike Huckabee, according to local media reports, has also said Sprint should not fall into SoftBank’s hands due to links with Chinese supplier Huawei, which he thinks poses a national security threat.

To placate US authorities, however, SoftBank has already said it will not use Chinese suppliers in Sprint’s network.