Oliver Callan is hosting the Ryan Tubridy Show on RTE Radio 1 this morning as Ryan is suffering from a "persistent cough".
The funnyman revealed he will be filling in for Tubs as he gets his illness "checked out".
And he reassured listeners that Ryan will "hopefully" be well enough to present this week's Late Late Show.
Speaking on RTE Radio 1 this morning, Oliver explained: "Ryan has had a persistent cough over the last few days and he's getting it checked out so no need to worry.
"He's getting it checked out and hopefully he will be back on the Late Late Show this Friday, hale and hearty and doing what they've been doing over the last few weeks which I think has been very helpful to a lot of us and very entertaining as well.
"And probably, more importantly, making it feel like a Friday so that we can keep track of the days and the weeks in this thing.
"Because as the Taoiseach said yesterday, we're in it for the long haul and we're in it together.
"So no need to panic, in the meantime, we will continue to listen to your thoughts and ideas on this national state of solitary confinement."
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