BRUSSELS, July 14 (Reuters) - The European Commission stuck to its guns on Friday, saying it was not reconsidering EU antitrust chief Margrethe Vestager's pick of a U.S. economist to a senior job helping to oversee Big Tech despite criticism from French ministers and EU lawmakers. Fiona Scott Morton, 56, the former chief economist at the U.S. Department of Justice during former President Barack Obama's tenure, will take up her three-year stint on Sept. 1 when the current chief economist, Pierre Regibeau, retires. She will be the first non-EU national, first U.S. national and first woman for the job. They cited the strategic importance of the post, potential conflicts of interest due to Scott Morton's previous work with Big Tech, and her previous public antitrust comments. Head of the centre-right group European People's Party Manfred Weber, president of the liberals' group Renew Europe Stephane Sejourne, head of the socialists group Iratxe Garcia Perez and the heads of the green party Philippe Lamberts and Terry Reintke said they opposed the new hire.

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Persons: Margrethe Vestager's, Fiona Scott Morton, Barack Obama's, Pierre Regibeau, Vestager, Scott Morton's, Dana Spinant, European People's Party Manfred Weber, Europe Stephane Sejourne, Iratxe Garcia Perez, Philippe Lamberts, Terry Reintke, Scott Morton, Foo Yun Chee, Jan Harvey Organizations: European Commission, Big Tech, U.S . Department of Justice, EU, European People's Party, Thomson Locations: BRUSSELS, U.S, Europe