Thousands of people on Saturday staged the biggest protest yet against Guatemalan president Alejandro Giammattei, with some setting fire to Congress, fuelled by anger over cuts in the 2021 budget just as the country reels from back to back storms.

Waving Guatemalan flags and signs declaring “Giammattei, resign,” demonstrators called for Giammattei to veto the budget, which lawmakers approved at dawn last Wednesday even as Hurricane Iota was drenching parts of the Central American country still grappling with the destruction of a prior storm...