UPDATE 2-Covidien plans to move executive office to Ireland

(Adds details of plan, comments from analyst and company spokesman, share activity, byline; changes dateline from NEW YORK)

By Susan Kelly

CHICAGO, Dec 23 (Reuters) - Health care products company Covidien Ltd (COV.N: Quote, Profile, Research) is moving its headquarters to Ireland to take advantage of the country's favorable tax structure and location, it said on Tuesday.

The move from Bermuda should not affect Covidien's U.S operations or workforce, or its financial results, the company said in a statement.

Shares of Covidien fell nearly 5 percent on expectations that the company would be removed from the Standard and Poor's 500 index as a result of the headquarters relocation.

Covidien spokesman Eric Kraus said S&P would make that decision.

Ireland has a "long history of international investment and a good network of tax treaties" with the United States, European Union and other countries where Covidien has major operations, the company said.

"Incorporation in Ireland will offer increased strategic flexibility and operational benefits as we continue to expand the rapidly growing international portion of our business," Chief Executive Richard Meelia said.

Covidien says it foresees strong growth in markets outside the United States, which now account for about 50 percent of its sales.