Investor Qatar has said today it has not yet decided whether to support Glencore's revised bid for Xstrata.

It said it would announce a decision in due course when it had considered all the implications.

Commodities trader Glencore laid out what it said was a final $36 billion takeover offer for Xstrata on Monday, following an unexpected turnaround that ended months of stalemate with the miner's second-largest investor, Qatar.

"Qatar Holding will make its decision in due course after giving careful consideration to the implications of the proposed management changes, the other elements of the Revised Proposal and the views of Xstrata's board," it said in a brief statement.

"QH will make its decision in due course after giving careful consideration to the implications of the proposed management changes, the other elements of the revised proposal and the views of Xstrata's board."

Glencore, which already owns just over a third of Xstrata, confirmed on Monday that it was raising its bid to 3.05 new shares for every Xstrata share held, up from 2.8, which Qatar had said was not enough.

The revised offer represents a 27% premium to the ratio at which Glencore and Xstrata were trading last week, when the market believed the deal would collapse.

It was released after a weekend of intense negotiations and has been seen by those close to the deal as more conciliatory and less aggressive than proposals presented to Xstrata's board on Friday, just minutes before the miner's shareholders were due to vote on Glencore's original bid.