July 24 (Reuters) - German Chancellor Friedrich Merz is set to appoint Nina Warken as his new chief of staff, he told journalists on Friday, a pivotal choice to tighten control of day-to-day governing after moving Thorsten Frei to lead the CDU/CSU parliamentary faction.
Carsten Linnemann would be appointed health minister, he added.
(Reporting by Andreas Rinke, Linda Pasquini and Ludwig Burger, Editing by Miranda Murray)