Iran said on Sunday that within hours it would breach the limits on uranium enrichment set four years ago in an accord with the United States and other international powers that was designed to keep Tehran from producing a nuclear weapon.

The latest move inches Iran closer to where it was before the accord: on the path to being able to produce an atomic bomb.

President Trump withdrew the United States from the accord last year and in May dealt a crippling blow to Iran’s economy by implementing sanctions intended to cut off its oil sales any where in the world.

In recent weeks, Tehran has retaliated by making deliberate but provocative violations of the accord as part of a carefully calibrated campaign to pressure the West into eliminating sanctions that have slashed the country’s oil exports and crippled its economy.