Xstrata has asked its bankers to study the viability of a new 3 billion pounds ($4.90 billion) bid for platinum producer Lonmin , according to the Observer newspaper.

The report, which did not cite any sources, said that the mining giant, which has been restricted from making a new bid lower than the 3,300 pence it proposed for 12 months because of takeover rules, would move for Lonmin again next month after instructing JP Morgan and Deutsche Bank to conduct a feasibility study ahead of a possible bid.

Xstrata bought a 24.9 percent stake in Lonmin last year.

Lonmin's shares rose last week on speculation that a bid was imminent.

However, analysts at Liberum Capital said they thought Xstrata was unlikely to move for Lonmin because a cash purchase of a 75 percent stake would take its net debt to around $16.8 billion or 50 percent gearing.

Xstrata declined to comment when contacted by Reuters.

($1=.6123 Pound)

(Reporting by Rhys Jones; editing by Karen Foster)