The twins, who found fame on The X Factor in 2009, called Jim out on Twitter after he shared a short video of the protest and praised the “great turnout”.
Making a pun on The Corrs’ 2000 hit, Jedward – real names John and Edward Grimes – wrote: “G’wan leave the whole country ‘breathless’ from Covid because of your idiotic behaviour.”
Jim, who founded The Corrs in 1990 with his three sisters Andrea, Sharon and Caroline, hit back, writing: “Shut up you fools and grow a brain between you.”
Jedward continued their wordplay on past Corrs singles, responding: “Why don’t you just go and ‘Runaway’ and FYI your sisters never needed you please leave the band.”
Drawing a comparison with a 1980s pop duo, Jim replied again, writing: “Ireland’s Millie Vanillie have spoken and I shall hand in my notice forthwith.”
He added: “But lads, I just want to say…” before sharing a link to the Corrs’ song I Never Loved You Anyway.
Jedward then wrote: “Twitter fights are so pathetic! We don’t have time! We’re right you’re wrong.
“Wear your mask and wash your hands to whoever needs to hear this.”
Addressing their own followers, Jedward tweeted: “Everyone has the right to protest but it’s not peaceful or making change when the consequences are more deaths! That’s not democracy it’s murder!
“When your core message is wrong you have no legs to stand on! There’s only one right in this fight against Covid, so don’t even try to question it!
“Change your attitude and get with the times,” they added.