The presenter, 55, was off from the show last week after suffering a shortness of breath, cough and fatigue.
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But on his return, Piers returned to his usual fierce commentary, which has left viewers divided in the wake of Boris Johnson’s address to the nation yesterday.
Susanna said: “Welcome back to the programme. How are you feeling?”
Piers added: “I feel fine except I feel extremely frustrated by what I watched last night.
“I don’t know where it leaves us and I don’t understand the sequence of events here.
“Boris Johnson clears 15 minutes of prime time, Sunday night television to address the nation.
“And you expect when you get that amount of time on a Sunday night at seven o’clock you would get loads of great detail that clears everything up.
“Instead we got a load of his usual flim-flam, his bluster, his bellicose, fist-pumping rhetoric. But when it gets to the detail, I don’t know where it lives us.”
Fans were divided by Piers’ return, with one person saying: “Must admit you got it right today off the bat we’re all confused I was it’s so damaging to the public right now that message !”
Another added: “That’s the best thing Piers has said in weeks”
A third said: “Welcome back Piers. Don’t forget in Wales and Scotland we are still being told to stay home thankfully”
However, others weren’t as charitable, with one saying: “The Morgan ramblings are getting evermore unhinged. Who’d have thought that was possible?”
A second said: “Negativity. Let me spell it out for you. Boris said “Further details will be explained in the commons tomorrow and at the 5PM briefing”. There is no confusion, wait and find out what he’s going to say today just like we all have to do. You’re losing your grip.”
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But most of Britain’s strict lockdown measures will stay in place for now as it’s still too soon to make any major changes, he said.
Piers tested negative for coronavirus after developing symtoms.
He told fans last week: “UPDATE: My COVID-19 test was negative.
“I was advised to take the test by my doctor after developing possible coronavirus symptoms, and was entitled to do so as a Govt-designated essential worker.
“I’ll be back on @GMB as soon as my doctor advises I’m OK to return to work.”