Washington DC - President Donald Trump scrapped two bills this week, exercising his veto power for the first time during his second term to reject a water pipeline and the expansion of Native American territory.

Trump vetoed the bipartisan-backed bills on Monday, the White House announced on social media. Both the Senate and the House would need to pass the bills again by a two-thirds majority to override the president.

One of the bills, the Finish the Arkansas Valley Conduit Act, aimed to complete a decades-long plan to pipe clean water to Colorado's Eastern Plains.

In his letter to Congress explaining the veto, Trump argued it would cost too much, and said he was "preventing American taxpayers from funding expensive and unreliable policies."

The pipeline was initially proposed during John F. Kennedy's presidency in the 1960s, and the vetoed bill had received unanimous support from both houses of Congress.

It was backed by Colorado's two Democratic Senators and by Republican Representatives Jeff Hurd and Lauren Boebert, the latter of whom reacted angrily to the decision.

The White House said Trump also vetoed the Miccosukee Reserved Area Amendments Act.

The measure sought to extend the Miccosukee Native American Tribe's control over a section of the Everglades National Park in Florida called Osceola Camp.

The tribe joined a lawsuit this year against an immigration detention center in the Everglades referred to as "Alligator Alcatraz." A federal judge has ordered much of the site to be dismantled, effectively shuttering the facility.

Trump said the tribe was not authorized to inhabit Osceola Camp and that his administration would not allow taxpayer money to be spent on "projects for special interests," especially for groups "unaligned" with his immigration policies.