The London Stock Exchange Group (LSE) and Deutsche Börse agreed terms for a "merger of equals" on Wednesday, creating Europe’s biggest securities-markets operator worth more than $30bn (€27bn).

The tie-up, still subject to antitrust clearances and other regulatory approvals, will create a powerhouse of trading in stocks, bonds and derivatives and post-trade services.

Under the terms of the deal, LSE shareholders will own 45.6% of the new holding company, named UKTopCo, with Deutsche Börse shareholders owning the rest.

LSE chief executive Xavier Rolet, who plans to step down after the merger is complete, said the two firms were "creating an industry-defining combination".

Cost savings of €450m a year are expected, about 20% of the combined group's operating costs of €2.2bn last year.

The newly-merged company will keep both the London and Frankfurt headquarters, with new holding company based in London.

Carsten Kengeter, current head of Detusche Borse, will become chief executive.

The merger deal is expected to be completed either by the end of this year or the first quarter of 2017.

A joint statement by both exchanges on Wednesday outlined the expected benefits to each business area.

LSE's FTSE Russell and Deutsche Börse's are “well positioned” to respond to growth trends in the asset management industry, including the shift to passive investment tracking indices.

CCP clearing houses LCH.Clearnet and Eurex Clearing will now fall under one roof, a combination which will “promote safety and transparency" for the financial markets”, the pair added.

Both groups also plan to work on a portfolio margining service between OTC and listed rate derivative clearing markets.

Earlier this month, Intercontinental Exchange (ICE), which owns the New York Stock Exchange, said it was considering making a bid for the LSE.