sorry to keep / to have kept you waiting

[Tan Elaine]

If I am talking on the phone and then ask the caller to hold the line as I have to attend to something urgent, which is the correct apology when I get back to him/her on the phone?

1. I am sorry to keep you waiting.

2. I am sorry to have kept you waiting.

Thanks.

[Rover_KE]

You will hear both from native speakers.

2 is more grammatical, but who cares? It's the apology that matters.

Rover