Latest: Nato to expel seven Russians over spy poisoning

Latest: Nato chief Jens Stoltenberg says the alliance will expel seven staff from the Russian mission.

Update - 3.03pm: Nato chief Jens Stoltenberg says the alliance will expel seven staff from the Russian mission.

3.03pm: Russia vows to retaliate over expelled envoys A top Russian diplomat has said Moscow is preparing a "tough response" to today's announcement by the United States that it is expelling 60 Russian diplomats.