How do I suggest STI testing without my partner hearing an accusation?

My partner and I have been discussing whether to stop using condoms. When I suggested both getting advice about STI testing first, he said, "What do you think I've been doing?"

We are both adults and have had previous partners. I am not alleging that he has had another partner during our relationship. I also do not want the conversation to rest on neither of us currently noticing symptoms.

[NHS guidance says many STIs have no symptoms](https://www.nhs.uk/conditions/sexually-transmitted-infections-stis/). I plan to contact a sexual health clinic about which tests and timing are appropriate for me, and I want him to consider his own advice too. We are continuing our current precautions while discussing this.

How would you make the request mutual without turning test results into a certificate of trust? I would rather talk about what we know and what advice we need than have either person confess to something they have not said happened.