Exchanges are considering merging to cut costs

Of votes cast, 99.68% supported the motion to return 200 pence per share to investors promised when the LSE fended off Australia's Macquarie bank bid.

The news comes as the New York Stock Exchange considers buying shares from certain LSE investors, say sources.

It is speculated that NYSE could be trying to block a rival offer.

'Very rare assets'

Some argue that the NYSE might be trying to prevent its US rival Nasdaq, which recently acquired 14.9% in the LSE, from acquiring further shares.

Nasdaq recently increased its stake in the LSE by acquiring about 35 million LSE stocks from Threadneadle Asset Management as well as 2.7 million from Scottish Widows Investment Partnership.

The shares were valued at �11.75 per share, in a deal worth �447.7m ($780m).

"These are very, very rare assets, particularly an exchange with the depth and global reach of the LSE," said Nick Train, a fund manager of the Finsbury Growth & Income Trust.

The acquisition followed a rejection in mid April by LSE of a �2.4bn bid by Nasdaq.

It's always been clear that if there were a takeover [of the LSE], it needed to be at a very high price Nick Train, fund manager

Nasdaq is allowed to buy a further 10% in LSE, which would raise its stake to 24.99%, before launching another bid.

For its part, Citigroup, the advisor to NYSE, has contacted LSE shareholders including DE Shaw and Scottish Widows Investment Partnership to find out if they were interested in selling stakes in the exchange for at least �11.75 a share, a source told the Reuters news agency.

Such a deal would value LSE at about �3bn ($5.3nb), but sources said the shareholders had declined the offer. NYSE made no comment.

"It's always been clear that if there were a takeover [of the LSE], it needed to be at a very high price," said Mr Train.

Exchange consolidation

Others meanwhile have speculated that both US exchanges could team up together to acquire the LSE.

Desires to cut costs and increase trading volume have increased interest in possible mergers between exchanges.

It has also been suggested that the NYSE could merge with Euronext, the stock exchange based in Paris, Brussels, Lisbon and Amsterdam, or Germany's Deutsche Boerse.