ROME/PARIS (Reuters) -European aerospace groups unveiled an initial deal on Thursday to pool their loss-making satellite manufacturing activities, combining forces after months of negotiations to counter the runaway growth of rivals led by Elon Musk's Starlink.

The keenly awaited deal between Airbus, Thales and Leonardo aims to forge a new venture starting from 2027, subject to approval by European regulators who have resisted such moves in the past.

The unnamed new entity will employ 25,000 people across Europe with annual revenues of 6.5 billion euros ($7.58 billion), based on 2024 figures, the companies said in a statement.

Airbus will hold 35%, while Thales and Leonardo will each hold 32.5%, the statement said, adding it would operate under joint control "with a balanced governance structure".

The space combination is expected to generate "mid-triple digit" millions of euros of synergies on operating income per year, starting after five years, the companies said.

Code-named "Project Bromo," talks between the three aerospace groups started last year in a bid to copy the co-operation model of European missile maker MBDA, which is owned by Airbus, Leonardo and BAE Systems.

Europe's top satellite makers have long competed to build complex spacecraft in geostationary orbit but have been hit by the arrival of cheap tiny satellites in low Earth orbit.

The CEOs of the three companies said in a joint declaration that the merger would help governments ensure "Europe's autonomy across the strategic space domain".

The deal will combine manufacturing and services activities of Thales Alenia Space and Telespazio - two joint ventures between Leonardo and Thales - as well as various Airbus space and digital businesses, the remaining space activities owned by Leonardo and Thales SESO.

The companies, who have already cut a combined total of some 3,000 jobs in space, made no mention of any further job cuts, but said unions would be consulted on the project.

Reuters reported earlier this week that the three aerospace groups had reached a framework deal on a proposed tie-up of their satellite businesses.

Agreement between the three companies - each of which has had periods of prickly relations in the past - was salvaged after sources familiar with the matter said the talks had hit obstacles over governance and valuation during the summer.

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