Nobody at Gas Natural was immediately available to comment. Repsol has denied the claims, saying any such talk is "unfounded".
Repsol soars on Gas Natural talk
Shares in Spanish producer Repsol YPF leapt by 7.6% in trade today on market rumours that utility Gas Natural could bid for the company at a price of €30 ($40.10) a share.
23 March 2007 12:26 GMT
Updated
23 March 2007 12:26 GMT
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