Money manager BlackRock Inc's chairman Larry Fink said he intended to stay with the firm he co-founded, after news reports tipped him as a candidate to takeover the chief executive slot at Merrill Lynch.

Merrill named John Thain, the head of NYSE Euronext, as its new CEO on Wednesday, replacing Stan O'Neal who was ousted as chairman and CEO last month after Merrill wrote down $8.4 billion in assets during the third quarter.

I am honored to serve as BlackRock's chairman and CEO and I am fully and exclusively focused on and committed to BlackRock, Fink said in a letter to employees, which was obtained by Reuters on Thursday.

His comments would appear to rule him out for the top job at Citigroup Inc, to which he was also linked after the retirement this month of CEO Charles 'Chuck' Prince following billions of dollars in subprime mortgage losses at the firm. Thain had also been considered a leading candidate for the Citigroup post.

A source with knowledge of the matter said Fink was not in the running for the Citigroup post.

BlackRock, Fink and Merrill have not publicly acknowledged that Fink was in the race for the top Merrill job. Two weeks ago, Fink told Reuters he was unaware of his candidacy and that he was a happy CEO of BlackRock.

People thought he might be inclined to take it, said Rachel Barnard, an analyst at research firm Morningstar.

In comments after Thain's appointment at Merrill, Fink said: Merrill Lynch is a valued strategic partner of BlackRock, and I look forward to working with John Thain to continue building on that strong relationship.

Fink, who co-founded BlackRock as a bond shop 19 years ago, had helped find Thain for the NYSE post after helping to persuade embattled former New York Stock Exchange Chairman Dick Grasso to step down. BlackRock is now the largest listed U.S. asset manager and Fink owns a stake worth $300 million in it.

Fink also apologized to employees, calling media coverage of his candidacy a distraction for all of us. I was not looking to be considered for other positions or for media attention, he said.

Merrill owns 49 percent of BlackRock and is also its largest client. Banking firm PNC Financial Services Group owns 34 percent of the firm.

BlackRock shares edged up 30 cents to close at $196.50 on Thursday amid a generally weak market.

Investment NYSE Euronext Merrill Lynch