Some of the thousands who stormed the US Capitol on January 6, 2021, called for Pence to be hanged, forcing him to seek a safe location.
Trump has already declared his intention to seek a new term as president in 2024 elections, and Pence indicated he may challenge him for the Republican nomination.
The Gridiron Dinner is usually a light-hearted event with skits and musical entertainment, and Pence initially sought to poke fun.
“I will wholeheartedly, unreservedly support the Republican nominee for president in 2024 – if it’s me,” he said.
Near the end of his speech, Pence said there was one issue he would not joke about.
“The American people have a right to know what took place at the Capitol on January 6th,” he said, according to The Washington Post newspaper.
“But make no mistake about it, what happened that day was a disgrace, and it mocks decency to portray it in any other way.”
Pence’s sharp remarks aimed at Trump were unexpected at the gala.
“Was at the dinner and can confirm @Mike_Pence definitely caught the room by surprise--lots of dropped jaws,” tweeted Maryam Mujica, a former State Department official.