Trump Says He Will Announce His Running Mate at Convention

Donald J. Trump said he would announce his running mate next month at the Republican National Convention, a move that would add considerable suspense to a gathering that otherwise could lack for high drama.

Mr. Trump has told aides for weeks that he would like to use the convention for the announcement, though he has been more noncommittal in public.

In January, he told Fox News that he had decided on his running mate and suggested he would announce his decision on one of the network’s programs. In later interviews, he said he would unveil his choice closer to the convention, scheduled to start July 15 in Milwaukee.

A former reality TV star with a knack for building an audience, Mr. Trump waited until just days before the 2016 Republican National Convention in Cleveland to announce then-Gov. Mike Pence of Indiana as his running mate.

Last month, he told TMJ4 News in Milwaukee that there was “a pretty good chance” he would introduce his running mate during the convention, a timetable he seemed to settle on during a pair of interviews on Thursday.

“I’m going to do it in the convention,” Mr. Trump said in an interview with Dr. Phil McGraw, the television host and supporter of the former president.

He outlined a similar plan in an interview on Fox News. “I think I’ll announce who that person’s going to be during the convention,” Mr. Trump said. “I think that’s pretty normal, during the convention. It’ll be an interesting period of time.”

Mr. Trump has started to narrow the field of potential contenders even as his campaign has initiated a vetting process with a broader field of potential candidates, according to three people briefed on the process who insisted on anonymity to discuss private conversations.

According to these people,