Democrats said the Pence selection is "divisive".
The presumptive Republican nominee said in the tweet he will hold a news conference tomorrow at 11 a.m.
In an interview to Fox News Trump said he has not made a "final decision" yet. But he said Thursday he would delay the announcement because of the attacks in Nice, France. Ivanka Trump and her husband Jared Kushner also met privately with New Jersey Gov. Chris Christie Tuesday, NBC News reported.
Pence is a former conservative talk-radio host who once described himself as "Rush Limbaugh on decaf". Pence, the Washington Post's Jim Tankersley observed earlier this week, "voted for every free-trade agreement that came before him" as a congressman.
As a lawmaker, he chaired the Republican Study Group, a coalition of hard-core conservatives, which gives him solid bona fides among the grass-roots Tea Party wing of the party that has occasional doubts about Trump's ideological purity.
Donald Trump abruptly postponed plans to announce his vice presidential pick following a day of rampant speculation, citing the "horrible attack" in Nice, France, that left scores dead.
Clinton's campaign moved quickly to paint Pence as the "most extreme pick in a generation".
Podesta says Pence is known for supporting what Podesta calls "discriminatory politics and failed economic policies that favor millionaires and corporations over working families".
Throughout the selection process, Trump said he wanted a vice president who could help him lobby Congress on legislation.
A lot of the recent commentary on vice presidential choices slices and dices history to show that ultimately the choice of running mate doesn't make much difference.
The first-term Republican governor was seeking re-election. IN law prohibits an individual from appearing on the ballot for both a state and federal office.
As governor of Indiana, Pence has invited criticism for signing bills making it harder for women to have abortions.
Mike Pence joins Republican presidential candidate Donald Trump at a rally in Westfield, Ind., Tuesday, July 12, 2016. Trump said he'd instead hold a press conference Saturday at 11 a.m.in NY.
Trump and Pence have disagreed on a variety of topics during the Republican primary, and Pence endorsed Trump's rival, Texas Sen.
"Trump has great business experience", Qunell said.
Trump had originally planned to announce his running mate on Friday.
"I think that Mr Trump has reached a decision but he isn't prepared to announce it yet".
Mr. Pence amassed one of the most conservative records during his six terms in Congress, and was one of his party's few voices opposing President George W. Bush's attempts to expand the federal role in education and entitlement spending.
The convention's rules committee is dominated by Trump backers, as well as national and state GOP officials. Pence needs to file paperwork by noon Friday to take his name off the gubernatorial ballot so Indiana Republican leaders can pick a new candidate for governor.