Swiss commodities giant Glencore clarified on Monday its revised proposal for a merger with Swiss mining group Xstrata, saying it would not up its offer a second time. But in a concession to Xstrata chief executive Mick Davis, Glencore said that he could oversee the handover before making way for Glencore chief Ivan Glasenberg after six months. Glencore, which confirmed on Monday that its increased merger offering represented 3.05 new Glencore shares for each Xstrata share, also said that it would pay \"appropriate\" bonuses to 73 key Xstrata managers. In a statement released on Monday, Glencore said its increased offer represented a premium of more than 27 percent \"and it will not increase the merger ratio further\". This is \"a substantial premium for a company with a 34 percent\" stake in Xstrata, said the statement by Glencore, based in the canton of Baar in the centre of Switzerland. Responding to the Glencore proposal, Xstrata said on Monday it would \"consider carefully\" the proposal before deciding whether to put it to shareholders, giving a deadline of 0700 GMT on Monday, September 24. Ahead of Monday\'s developments, the blockbuster merger of the two Swiss firms appeared compromised in analysts\' eyes over the amount Glencore was willing to pay to tie up the deal. The Qatar Holding investment fund, which is the single biggest shareholder in Xstrata with more than 12 percent of its shares, has consistently called since June for a rate of 3.25 Glencore shares for one Xstrata share. If completed, the merger would create a commodities behemoth worth around 69.8 billion euros ($87.3 billion) according to current market capitalisation.