Our reporter Paul Brand is tweeting from the demonstration in Whitehall.
Campaigners fighting to save Lewisham hospital's A&E + maternity believe Dept of Health will announce decision 2moro on poss closure of both
MPs take front line in final demo outside Dept of Health to save Lewisham Hospital A&E and maternity services http://t.co/kYdcnz1h
Campaigners have also handed over a petition with 40,000 signatures against Lewisham closures
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Tubes, trains, trams, buses, cable cars, river buses, taxis and going by foot - your guide to getting around during the strike.
Union officials rejected a revised offer from Underground managers during a meeting at the conciliation service ACAS this afternoon.