use of infinitive or -ing form

In the sentence: I’m sorry, but I regret ____________(to tell) you are wrong about vegan food.

Should we use: to tell- I’m sorry, but I regret to tell you are wrong about vegan food.
And in this case do we have to use a comma?

Or should we use: I’m sorry, but I regret telling you are wrong about vegan food.

Which one is correct and why? Thanks :oops:

Hi Carvalho,

The comma suggests a short pause and would seem appropriate here.

There are two constructions here: I regret to tell suggests you are about to tell somebody something.

I regret telling you means you regret that you have already told/told somebody something.

Alan