The WSJ reports Sprint (S) has "received proposals from at least two banks" for financing a T-Mobile USA (TMUS) bid, and envisions valuing T-Mobile's equity at $31B (compares favorably to a current market cap of $26B).
Financing, of course, is only one of several challenges Sprint would face in merging with T-Mobile. The company and parent SoftBank (SFTBF) would have to negotiate a deal for Deutsche Telekom's (DTEGY, DTEGF) 67% T-Mobile stake. They would also have to win the blessing of FCC/DOJ regulators who seem to prefer having four nationwide carriers around, and appear to be pleased with T-Mobile's aggressive pricing.
In addition to acquiring Deutsche's T-Mobile stake, Sprint may need to backstop a possible refinancing of ~$20B worth of T-Mobile deal.