A leaked CIA briefing to the White House concludes that Iran retains significant ballistic missile capabilities, undercutting Donald Trump's claims that the regime's stockpile has been wiped out.

The regime retains roughly 70 percent of its prewar missile stockpile and 75 percent of its mobile launcher inventory, according to a confidential CIA analysis provided to Trump officials.

A US official told The Washington Post that Iran has recovered and reopened the vast majority of the underground storage facilities damaged in the opening stages of the war.

Sources added that Iran has not only repaired damaged missiles but has also managed to produce new ones.

The latest intelligence leak compiled this week contradicts Trump's remarks in the Oval Office yesterday, when he claimed Iran's 'missiles are mostly decimated, they have probably 18, 19 percent, but not a lot by comparison to what they had.'

Intelligence officials found that Iran can withstand the economic toll of Trump's naval blockade of the Strait of Hormuz for at least three to four months. 

Trump ordered the blockade despite the fragile ceasefire with Iran, aiming to pressure Tehran back to the negotiating table.

The strait's closure has triggered a sharp rise in US gasoline and global oil prices, leaving Trump under mounting political pressure to bring the war to a close before the economic toll deepens.

Despite the findings from Trump's own intelligence community, a senior US official continued to defend the blockade's impact.

'The President's blockade is inflicting real, compounding damage — severing trade, crushing revenue, and accelerating systemic economic collapse,' the official, who was not authorized to speak on the record, told the Washington Post. 

'Iran's military has been badly degraded, its navy destroyed, and its leaders are in hiding.'

Trump and Pentagon leaders have consistently touted the blockade's success, with the President calling it 'unbelievable' in the past 24 hours.

'The Navy has been incredible. The job they did … it's like a wall of steel. Nobody goes through,' Trump said.

Trump went even further a day prior after bragging that Iran's economy 'is crashing' and the regime's currency is so 'worthless' that it 'can't pay' their troops.  

Iran's ability to weather prolonged economic pain has outlasted the CIA's earlier projections, a source told The Washington Post.

'The leadership has gotten more radical, determined and increasingly confident they can outlast US political will and sustain domestic repression to check any resistance,' the source said.