Tulsi Gabbard, the Democratic US representative from Hawaii, said she will run for president in 2020, CNN reported on Friday.

“I have decided to run and will be making a formal announcement within the next week,” she said in an interview with CNN that is scheduled to air on Saturday.

Gabbard is a 37-year-old Iraq war veteran and the first Hindu and first Samoan-American elected to the US Congress. She said “the issue of war and peace” would be the main focus of her campaign.

Her office did not immediately respond to a request for comment.

Gabbard is popular with some liberals in the Democratic party but will have serious competition in what is expected to be a crowded primary field before the November 2020 election.

The US senator Elizabeth Warren, of Massachusetts, on 31 December announced she had formed an exploratory committee for a presidential run. The Democratic field could eventually include Senators Kamala Harris, Cory Booker and Kirsten Gillibrand, as well as the former vice-president Joe Biden. Julian Castro, Barack Obama’s former housing secretary, also formed an exploratory committee in December.

In the race to pick a candidate to run against Trump, Democrats will grapple with the tension between the party’s establishment and liberal wings that flared during the 2016 state-by-state nominating contests between Hillary Clinton and Bernie Sanders, an independent senator who ran under the Democratic banner.

Elizabeth Warren is among the Democrats running in 2020 – a contest that’s expected to be crowded. Photograph: Justin Wan/AP

Gabbard made headlines in 2016 by quitting a leadership post at the Democratic National Committee over the party’s decision to limit the number of debates between Clinton and Sanders. Analysts believed fewer debates benefited Clinton.

Clinton ultimately won the Democratic nomination but lost to Trump.

The congresswoman then endorsed Sanders for president, becoming one of the few members of Congress to do so.

Gabbard has also drawn criticism for secretly meeting with Syria’s president, Bashar al-Assad, during a 2017 trip to the war-torn country. Gabbard opposes removing Assad from power.