EADS Chief Executive Tom Enders said talks with governments over a proposed merger with BAE Systems were constructive and advanced, but acknowledged work remained to sell their $45 billion tie-up to investors.

Spelling out the rationale behind plans to create the world’s largest defence group, Enders told employees that EADS was trying to accommodate concerns of governments and offered reassurance after a drop in the company’s share price.

“I strongly believe this deal represents what is called a ‘perfect fit’: it doesn’t add complexity, it provides opportunity,” Enders said in an internal letter.

“Despite some initial critical reactions, word will soon go around that this deal makes good business sense.”

He said Airbus parent EADS and Britain’s BAE Sytems, which have been given until Oct. 10 to say whether or not they plan to pursue the merger, were in good shape to be able to announce more details to markets and employees “probably soon”

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