The pair were matched up to present an award, but things took a turn once they arrived at the podium and attempted to banter with each other on stage.
Turning to Goulding, Grennan commented on her plastic chest-piece and asked if the anatomic piece was based on her "real" body.
Grennan responded the following day, posting on Twitter that it was an inside joke between the two singers, and that 'nerves got the better of us'.
Love ya @elliegoulding What started as a joke between Ellie and I before we went on stage came out all wrong. The nerves got the better of us, but that does not excuse what was said, and I sincerely apologise to anyone who was offended - that’s not me at all, and I am sorry x https://t.co/iylZTQ4TR1
— Tom Grennan (@Tom_Grennan) February 12, 2023
Goulding also responded tweeting that she was not offended by Grennan's comments, and that they were just 'having a bit of fun'.
"I love what you're doing... are they your real boobs?" he questioned during the live show on Saturday.
An unimpressed looking Goulding responded: "These are not mine, no. I wish! Mine are a lot further apart."
Viewers called out the misogynistic comment online immediately, deeming it "inappropriate" and "cringeworthy".
"Did Tom Grennan actually ask Ellie Goulding about her tits on TV? Really? What year are we in?" wrote one fan on Twitter. "And does he know he’s on cam? Also, she is a giant and he is an ant. Buh bye."
A second agreed and added: "Tom Grennan really thought it was cool to chat about Ellie Goulding’s boobs? Nah, I thought we were past this."
"Tom Grennan asking Ellie Goulding if they were her real boobs while presenting an award was super weird, uncomfortable and creepy. WTF?!" said a shocked third.
Thankfully the pair seemed to brush off the moment, and later laughed together as they continued their presenting duties.
Grennan was later up for best alternative award, which he lost to band Wet Leg.
This year's Brits was dominated by Harry Styles, Beyonce and Wet Leg, who all took home the major awards across the evening.
When picking up artist of the year, Harry Styles acknowledged the controversy around the all-male nominees, by paying tribute to stars including Becky Hill, Mabel, Rina Sawayama and Charli XCX in his speech.
This article was updated on Monday, 13 February, to reflect the comments of Ellie Goulding and Tom Grennan.
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