One person tweeted: "Does she not understand basics of UK parliament..."
The former Labour leader will host four days of talks, workshops and performances to highlight ways to tackle the climate emergency.
Labour's Taiwo Owatemi said she was "greatly concerned" by Kathleen Stock's trustee role in the group LGB Alliance.
The ex-health's secretary's appointment has sparked criticism after it followed a damning report into the UK's response to the pandemic.
Ed Miliband Reminds Us Starmer’s Driving Test Fail Could Have Been Worse: ‘It’s Hardly The Bacon Sandwich’
The former Labour leader was quick to defend Starmer after his embarrassing HGV moment.
The Greater Manchester mayor also dismissed accusations that he undermined Keir Starmer at Labour's conference in Brighton.
"I don’t know, it’s a yikes from me you guys."
The cabinet minister also defended Angela Rayner's "scum" comments, saying it was "late at night".
Powell: "I was a state educated, northern girl doing science."