Dish moved closer to securing $9 billion in backing for its $25.5 billion bid for Sprint, according to the Wall Street Journal.

The US bidder has received commitment letters from five banks, including Barclays Bank and Jefferies & Co, to back its bid, according to people who are familiar with the matter.

Dish has now secured close to $12 billion, if $2.6 billion in bonds raised last week is also included.

However Dish has not paid any commitment fees to the banks as yet and will not owe them any money unless they make use of the loans, sources said. Charlie Ergen, Dish’s chairman, is reluctant to pay such fees until it was the last obstacle before Sprint backs Dish’s bid as “potentially superior” to rival SoftBank’s.

Meanwhile SoftBank is pushing ahead with regulatory approval. It has now received all the necessary approvals from state regulators for the Sprint acquisition, with the most recent coming the California Public Utilities Commission. Applications were filed with 23 state regulators, plus the District of Columbia in November 2012.

SoftBank and Sprint “continue to work closely” with the Federal Communications Commission and other Federal agencies, which have still to approve the transaction.

Parallel to regulatory approval, the Japanese company is attempting to gain political backing for the deal. A Bloomberg report said SoftBank was prepared to offer the US government a veto over a director who would sit on the Sprint board and keep an eye on national-security issues should the takeover proceed.

SoftBank has already said it will not use telecoms equipment supplied by Huawei, the Chinese firm who causes such unease in US national-security circles. The Japanese firm has previously told US politicians that it would remove the Chinese vendor’s equipment from the network of Clearwire, the operator in which Sprint is trying to buy the 50 per cent it does not already won.

Removing Huawei equipment could cost SoftBank up to $1 billion, according to the Wall Street Journal, who spoke with people familiar with the situation.