The US military has drawn up plans to potentially use the GBU-43/B Massive Ordnance Air Blast, known as the mother of all bombs, against Iranian energy and nuclear sites if combat operations resume.
The 21,600-pound weapon is the most powerful non-nuclear bomb in the US arsenal, but officials have questioned its effectiveness against deeply buried nuclear facilities protected by granite.
President Donald Trump has directed the development of additional strike packages as he seeks a strategy to end the conflict without appearing to abandon US objectives ahead of the midterms.