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LONDON, Dec 17 (Reuters) - European shares paused after a record run on Tuesday as a sales warning from Unilever and concerns that Britain's Prime Minister Boris Johnson could take a hard stance on the transition period for Brexit dented UK stocks.
The FTSE 100 slipped 0.2% by 0817 GMT, handing back gains after its strongest rally in nearly a year on Monday after reports that Johnson will use his control of parliament to outlaw any extension of the Brexit transition period beyond 2020. The UK's domestically-focused mid-cap index was down 1.1%.
The broader European equities index, down 0.5%, came off record highs. Consumer goods giant Unilever slid 5.9% after it warned that 2019 sales would grow slightly below its expectations, citing tough trading conditions in West Africa and a slowdown in south Asia.
Europe's personal & household goods sector fell 1.9%.
Airbus rose 0.5% after rival Boeing said it would suspend production of its best-selling 737 MAX jetliner in January, although shares in aero parts makers Safran and Melrose fell 2.3% and 0.6%, respectively. (Reporting by Sruthi Shankar in London Editing by Gareth Jones)