Pacquiao and trainer Freddie Roach commented on their preparation for the May 2 fight against Floyd Mayweather in Las Vegas, with the Filipino legend saying it was "very good".
"We are ready to go. We had a great training camp and good sparring partners," Roach said of the fight.
Shortly after, though, Arum took control of proceedings.
"Oh (expletive)," Arum said as soon as he heard the first question would come from Eximaner.com's Michael Marley.
"Do this call some other time. Let's reorganise and do this some other time, please."
Then, reporters were told that Pacquiao had completed a sparring session over 12 rounds on Saturday, but no mention was made over tickets.
Promoters Top Rank released a statement earlier saying that the call system crashed due to the high traffic.
"At the top of the hour there were a massive number of calls from the media," Top Rank said in a statement.
"Our conference call system, which had worked for years, went down and we were unable to communicate with our operators. This was very unfortunate and we apologise."
After the Pacquia teleconference was called off, Arum told Kevin Iole of Yahoo Sports that the format of the call was undesirable and that only a small group of news reporters should be included in similar events in future.
"It was going to be an absolute disaster. I said we either do it the right way or we won't do it. The best way is to get four or five of the top guys and put them on the phone. I didn't want Manny on there having to listen to all this nonsense."
At the time of writing, no date has been set for the proposed rescheduling, although Mayweather has a similar conference call on Wednesday.