LSE and Deutsche Boerse to hold merger votes after UK's EU poll -sources

(Adds Deutsche Boerse shareholder vote detail, Kengeter comment)

LONDON/FRANKFURT, May 12 (Reuters) - London Stock Exchange (Other OTC: LDNXF - news) Group (LSEG) and Deutsche Boerse (LSE: 0H3T.L - news) will let shareholders decide on their proposed $30 billion merger after Britain's June referendum on European Union membership, three sources familiar with the matter said.

No final decision has yet been taken about the exact date of the shareholder votes, but both exchanges will give investors the opportunity to see the outcome of Britain's June 23 poll before they decide on the proposed tie-up, one source said.

LSEG and Deutsche Boerse declined to comment on the dates for the votes on the merger, which are likely to be announced in late May or early June, another of the sources said.

Initially there were some expectations that LSEG would hold a shareholder meeting to approve the merger with Deutsche Boerse before the British referendum.

This would have forced U.S (Other OTC: UBGXF - news) . group Intercontinental Exchange (NYSE: ICE - news) (ICE) to file any counterbid seven days before that meeting, with Britain's future still very much in doubt.

For ICE, LSEG would be a more attractive target with Britain inside the EU.

But earlier in May, ICE, owner of the New York Stock Exchange, said it was shelving plans to make a counterbid for LSEG, giving the British exchange more time to finalise its merger documents with Deutsche Boerse.

Deutsche Boerse still needs to file a full set of merger documents with German regulators, which could take several weeks.

The German exchange would not hold an actual meeting but open a tender offer period, during which shareholders are given a deadline to back or reject the deal.

A 75 percent majority in votes received is needed for the deal to go ahead, a process that is likely to be completed by late July.

The two European exchanges have presented their proposed deal as "Brexit" proof given their combination would straddle the EU and Britain, should it leave.

But bankers and politicians in Frankfurt are concerned the tie-up could undermine Germany's financial centre, citing the planned seat of the merged group in London and a possible UK exit from the EU.

"We are hopeful that this merger is going through," Deutsche Boerse chief executive Carsten Kengeter said at a conference in Frankfurt on Thursday.

"The dual headquarter structure of Frankfurt and London is a firm and important element of the overall structure," he added. (Reporting by Sophie Sassard, Anjuli Davies, Arno Schuetze, Andreas Kroener, Jonathan Gould and Huw Jones,; Editing by Mark Potter and Alexander Smith)