UPDATE 1-INTERVIEW-Mexico Senate sees oil reform draft next week

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By Jason Lange

MEXICO CITY, April 3 (Reuters) - Lawmakers from Mexico's ruling party will have a draft oil reform proposal ready next week with clauses to encourage drilling in deep-water oil fields on the U.S. maritime border, a senior senator said on Thursday.

Sen. Ruben Camarillo, the National Action Party's point man for writing the proposal, told Reuters the party was also "very seriously" considering measures to allow state oil monopoly Pemex to partner with other state firms in deep-sea oil.

"It's almost ready. We should have the final document within a week," Camarillo said in an interview. "It would be a financial and technological disaster to allow Pemex to go it alone in deep waters."

Camarillo said the party was studying ways to lure foreign oil majors into working with Pemex in deep waters that did not include concessions or risk contracts, which leftists oppose, as well as measures to boost investment in pipelines.

Pemex, a top supplier of crude to the United States, wants to develop potentially huge deep-water fields in its half of the Gulf of Mexico to stave off declining reserves and production.

However, it says it could get at the crude in half the time if legislation was passed to allow it to form joint ventures with foreign companies, be they private oil companies or state-owned like Brazil's Petrobras.

As lawmakers discuss the issue, many in the party, known as the PAN, have picked out deepwater oil fields on the border with the U.S. Gulf of Mexico as being a priority, as U.S. drilling could suck oil over to the other side.