I would remain calm and polite while apologizing to the client for the technical difficulties. I will get their meeting details and promise to follow up as soon as possible to continue the discussion. I would then contact the internet service provider to report the issue and get an estimated timeline for resolution. Once back online, I would immediately call the client, thank them for their patience, and continue the meeting. I would also report the internet downtime to the relevant teams to diagnose and prevent future occurrences.