UPDATE1-INTERVIEW-Mexico's PRI opposition open to energy debate

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By Catherine Bremer

MEXICO CITY, Jan 22 (Reuters) - Mexico's key opposition Institutional Revolutionary Party (PRI) is open to all ideas for energy reform, including a constitutional change, the party's general secretary Jesus Murillo said on Tuesday.

The PRI, whose position is crucial in congressional votes, remains firmly opposed to privatizing state oil monopoly Pemex, but would back private-sector alliances if that would bolster flagging reserves, Murillo told Reuters as lawmakers sat down this month to discuss a new energy law.

Conservative President Felipe Calderon, of the National Action Party (PAN), is keen to pass a law in the February-to-April congressional session that will spruce up how Pemex operates and boost its exploration activities.

But lawmakers are split over whether to limit changes to granting Pemex more autonomy, or go as far as permitting private partnerships in the state-controlled oil industry, which some say would require constitutional change.

"We are completely open today to any proposal," said Murillo, the No. 2 in the PRI, which was ousted in 2000 after 71 years in power and which carried out the 1938 nationalization of Mexico's oil industry.

The centrist PRI is now the second-weightiest party in the Senate and No. 3 in the lower house of deputies. Mexico's other main party, the left-wing Party of the Democratic Revolution (PRD), is against any constitutional change.

"We are ready to work with anyone that comes up with a good proposal," said Murillo. "Everything can be debated."