Ruben Barrales, president and chief executive officer of the San Diego Regional Chamber of Commerce, will not have his employment contract renewed, effectively terminating him Dec. 31.

Barrales, who has led the region’s largest chamber for six years, is expected to make the announcement of his departure today, according to sources.

Barrales, 50, was the former deputy assistant to President George W. Bush, and was recruited to the job by Herbert G. Klein, among other long-time chamber leaders. Barrales followed Jessie J. Knight Jr., who left the chamber CEO position to become an executive with Sempra Energy.

Barrales, who has effectively worked to raise the chamber’s and the city’s profile in Sacramento, Washington, D.C., and Mexico, serves on several nonprofit boards; he is a director of the Public Policy Institute of California.

He was hired in December 2006.

Knight left huge shoes to fill. That is why, in part, the chamber management committee wrestled with renewal of Barrales’ contract three years ago, according to some sources. Members complained the chamber’s focus had drifted from small business and city issues while Barrales was in Sacramento or Washington D.C. or Mexico. There were claims the chamber had adopted esoteric public policy positions based on unclear philosophical positions, including support of a failed tax increase supported by Mayor Jerry Sanders.

Barrales identifies as a Mexican American and is recognized as the first Latino person to serve on the San Mateo County Board of Supervisors. Barrales has also appeared in Hispanic Business Magazine’s “100 Most Influential Hispanics” list on three occasions within the last 10 years.

In 1998, Barrales was the Republican candidate for California state controller, though he failed to unseat Kathleen Connell. Although he lost, the campaign provided him national attention. In 2001, he was appointed as deputy assistant to the president and director of intergovernmental affairs in the White House by President George W. Bush.