The board of Xstrata has recommended that shareholders back the merger terms offered by Glencore.
Glencore had raised its offer after its first bid was opposed by key Xstrata shareholders, the BBC reports.
A merger would form one of the world's biggest metals and commodities firms, and could lead to other mergers in the mining sector.
Xstrata shareholders will now vote on whether to accept the offer of just over three Glencore shares for every Xstrata share.
