Even the heaviest US bombs are not powerful enough to destroy some of Iran's more fortified nuclear facilities, the Wall Street Journal
quoted US officials as saying Friday. The Pentagon is taking steps to improve its "bunker-busting" capabilities, they added.
The US' 30,000-pound (13,600 kilo) "Mass Ordnance Penetrator" (MOP) was specifically designed to be able to take out Iranian an North Korean nuclear facilities. According to the report, initial tests indicated that the bomb would be incapable of performing these tasks, either because of the depth of facilities or their recent reinforcement.The Journal
said that the MOP's test failure prompted a secret funding request by the Pentagon to Congress, seeking to enhance the bomb's capabilities. The US Defense Department has already spent approximately $330 million so far to develop about 20 of the bombs. The Pentagon is seeking an additional $82 million for upgrading purposes, according to government officials briefed on the plan.