UPDATE 1-Spain's Repsol in talks to sell Gas Natural stake to CVC - report

(Adds no comment from Repsol)

MADRID, Jan 10 (Reuters) - Spain's Repsol is in talks to sell its 20 percent stake in utility Gas Natural to investment fund CVC in a deal worth an estimated 4.1 billion euros ($4.9 billion), Expansion reported on Wednesday, without citing sources.

Repsol and Criteria Caixa, the holding company that owns Caixabank, agreed a near 4 billion-euro deal to each sell a 10 percent stake in Gas Natural to Global Infrastructure Partners in September 2016.

Caixabank holds 24 percent of Repsol.

Repsol declined to comment on the report.

($1 = 0.8385 euros) (Reporting by Paul Day; Editing by Rodrigo de Miguel and Mark Potter)