Feb 24 (Reuters) - Eduardo Mestre has stepped down as day-to-day head of Evercore Partners Inc's U.S. investment banking business, the New York-based company said in a regulatory filing.

Mestre, who joined the rapidly growing investment bank in 2004 after 25 years at Citigroup and Salomon Brothers, gave up his executive officer responsibilities because of conflicts when he was appointed this month to the audit committee of Comcast Corp, according to the filing.

At Evercore, he will assume a new title as chairman of global advisory and focus on client relations and "mentoring of senior Evercore personnel," while relinquishing all management and policy-making functions, the filing said.

Mestre, 63, was traveling on Friday and not available for comment, according to a person who answered his business phone. The company said it has no immediate plans to replace Mestre in his U.S. role.

Evercore was founded by former Lehman Brothers executive Roger Altman in 1996 as an advisory firm "free of the conflicts of interest inherent to large, multi-product financial institutions," according to its website. Mestre owns 1.9 percent of voting shares in the company, which went public in 2007, and like Altman has the right to receive a percentage of profits from investments made by one of Evercore's private equity funds.

Mestre, a senior managing director, received $4.9 million in total compensation in 2010, the last year for which Evercore has disclosed compensation. He will continue to be paid a salary of $500,000 per year and receive a bonus at the company's discretion, according to the filing.

Evercore ranked ninth as an adviser on U.S. merger and acquisition deals in 2011, ahead of UBS, according to Thomson Reuters. UBS on Friday said that its U.S.-based co-head of investment banking, Jimmy Neissa, will leave the company next month and be replaced as operating head by former Bear Stearns Cos Chief Financial Officer Samuel Molinaro.

Evercore is currently advising private equity firms Advent International and Goldman Sachs Capital Partners Fund on their pending acquisition of TransUnion Corp, and Kinder Morgan Inc on its planned takeover of El Paso Corp. Mestre, a graduate of Yale University with a law degree from Harvard, had been advising AT&T on its now-scotched acquisition of T-Mobile and is working with McGraw-Hill on the pending spin-off of its education division, according to his biography on the company's website.

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