He said the next 10 days would be crucial for the deal.
“We intend to come to a conclusion very soon. Investors are reacting very badly ... We cannot go on much longer,” he told an audience at the Royal Academy of Engineering in London.
EADS shares have shed more than 4 billion euros ($5.2 billion) in value since news of the talks broke last month due to investors’ misgivings. That means Lagardere’s 7.5 percent stake is now worth 300 million euros less than it was.
EADS and BAE shares rose around 1 percent on Monday.
Experts on Europe’s fragmented defence industry said Lagardere’s criticisms and a volley of negative remarks from Germany and elsewhere seemed designed to protect negotiating positions ahead of arm-twisting talks in coming days.
“It is like trade unions laying out their maximum demands before a pay negotiation,” a person close to the talks said.
“LEAKS CAN RUIN EVERYTHING”
German Defence Minister Thomas de Maiziere expressed concerns about a rise of potentially harmful rhetoric.