Mexico's oil minister resigns over oil-price cut

The sudden resignation of Jorge Diaz Serrano as head of Petroleos Mexicanos (PEMEX, the state oil company) brings to the surface a bitter feud within the Mexican government over oil policy.

It also could affect Mexico's coming presidential election and be a factor in this week's meeting of Mexican President Jose Lopez Portillo and President Reagan in Washington.

Mr. Diaz Serrano, as PEMEX's director- general and a close friend of President Lopez Portillo, was to have been part of the President's entourage -- and as such was expected to play a key role in developing a new Mexican-United States trade strategy.

Although Mexican oil policy has consistently maintained that no single country could receive more than half of Mexico's total oil exports, there is strong pressure on President reagan to urge Mexico to change that policy or at least to increase oil production, thus allowing US oil imports from Mexico to rise.

Mr. Diaz Serrano, who is regarded as a close friend of the US, was sympathetic to the latter approach and recently authored Mexico's decision to keep pumping oil at the current record level rather than comply with the OPEC plan to cut production by 10 percent. Although Mexico is not a member of OPEC, it has generally complied with OPEC decisions.

How the Diaz Serrano resignation will affect Mexican oil policy is unclear. But it puts a question mark over the Reagan-Lopez Portillo meetings June 8 and 9 .

It was Mr. Diaz Serrano's decision to cut the export price of Mexican oil by roughly $4 a barrel that led to his resignation, Mexican government sources say. The cutback went against OPEC urgings. More importantly, other officials, including Treasury Minister David Ibarra Munoz, opposed the price cut which is expected to trim Mexico's 1981 foreign exchange earnings by $1.5 billion.

Ibarra Munoz and Diaz serrano are among the likely presidential contenders in next year's election. It has always been chosen in Mexico's somewhat mysterious nominating system, under which the incumbent president, in consultation with former presidents and key political leaders, names his successor.