Swiss bank UBS AG (UBS) said Monday it will buy American International Group's (AIG) commodity index business, including the rights to the Dow Jones-AIG Commodity Index.

UBS said it would pay $15 million on closing and up to $135 million more over the next 18 months, depending on performance.

The purchase by UBS comes as a surprise, considering its recent divestments to get out of the commodities business.

"It seems a strange time to waste $150 million on something like this," Helvea analyst Peter Thorne told Dow Jones Newswires. Thorne rates the stock at accumulate.

The Swiss bank just last Friday announced the sale of a tranche of commodities operations to Barclays PLC (BCS). In December, UBS agreed to sell its Canadian energy and global agriculture businesses to J.P. Morgan Chase & Co. (JPM).

UBS shares closed at CHF13.33 Friday, down 10% in 2009 so far.

Company Web Site: http://www.ubs.com

-By Hans Schoemaker, Dow Jones Newswires; +41-43-4438045; hans.schoemaker@dowjones.com

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