“In utter hypocrisy, @BorisJohnson is 'concerned about Iran developing a viable nuclear weapon'. On the very same day he announces his country will increase its stockpile of nukes,” Zarif tweeted.
“Unlike the UK and allies, Iran believes nukes and all WMDs are barbaric & must be eradicated,” he added.
On Tuesday, the British government released a document saying it will increase the upper limit on the number of nuclear warheads in the military stockpile from 180 to 260.