UPDATE 1-Amex members approve acquisition by NYSE Euronext

(Adds background on deal, vote)

NEW YORK, June 17 (Reuters) - The American Stock Exchange said its members on Tuesday overwhelmingly approved the acquisition of the exchange by NYSE Euronext Inc (NYX.N), paving the way for the deal to close as early as August.

Amex members voted in favor of the sale by a margin of 695 to seven, with an 84 percent turnout.

Under terms of the deal, struck in January, NYSE Euronext, the parent of the New York Stock Exchange, will pay $260 million in common stock.

Amex members would also be entitled to additional shares based on the proceeds of the sale of its lower Manhattan headquarters, a few blocks from the NYSE. Last week Amex warned members that the building might be designated a landmark by the city of New York, which could affect its value.

The U.S. Securities and Exchange Commission must still approve rule changes related to the deal.

The deal was one of a number of big buys by the major exchanges in the past years during a period of consolidation and came less than a year after the New York Exchange merged with Euronext, an operator of four exchanges in Europe.

Acquiring Amex will allow NYSE to diversify further into options trading, exchange-traded funds and increase its listings of special purpose acquisition companies, of which Amex lists 75 SPACs.

NYSE Euronext expects the deal will realize "annualized run rate cost synergies" of more than $100 million within two years of closing.

Lehman Brothers Holdings Inc LEH.N is advising NYSE Euronext on this deal, while the Amex is being advised by Morgan Stanley (MS.N). (Reporting by Phil Wahba, editing by Maureen Bavdek)