According to The Times, western defense experts discovered Iran’s Fordow nuclear site is hidden deeper underground than previously estimated and therefore safe from conventional airstrikes.

The Times report, quoting Western defense experts, added that due to the “upgraded” progress of Iranian enrichment, Israel has to change their tactics to prevent a loss of up to 20% of its planes from a conventional air strike.

Defense experts claim Israel have two options, to either deploy special forces on the ground, or use ballistic missiles with tactical nuclear warheads, The Times reported.