Following the death of TV legend Cilla on Sunday, celebrities and high-profile figures who were close to Cilla or just simply admired her work, paid tributes via Twitter.
But Katie infuriated Twitter followers when she wrote: "If there are any celebrities who haven't yet tweeted their sadness over Cilla, please report to Sincerity Services immediately #rushtogush.
"I understand people love Cilla. But the race to proclaim this on Twitter is a curious thing."
Lord Sugar, who was among those tweeting condolences, quoted Katie's tweet and replied: "Why don't you shut up idiot!"
.@KTHopkins RT: understand people love Cilla. But the race to proclaim this on Twitter is a curious thing......why don't you shut up idiot!— Lord Sugar (@Lord_Sugar) August 2, 2015
Katie, who finished as runner-up in the last series of Celebrity Big Brother, replied: "Calm down @lord_sugar, you know you love your favourite Apprentice really."
But refusing to "calm down", Lord Sugar said Katie had gone "too far".
He tweeted in response: "Enough with the controversy BS you need to know where to draw the line. This was too far."
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