Former US Ambassador to the UN John Bolton told The Washington Post on Thursday that the only way left to prevent Iran from obtaining nuclear weapons is to support an Israeli military strike on the Islamic Republic.

Bolton said the soft approach taken by US President Barack Obama had only hastened the Iranian nuclear threat, and that today the only options that remain are to allow Iran to obtain nuclear weapons or intervene militarily.

With Obama almost certain to never order a military strike on Iran, that leaves only Israel.

Bolton urged Israel to decide quickly whether or not it will strike.

"Israel's decision of whether to use military force against Tehran's nuclear weapons program is more urgent than ever," said Bolton, adding that he is confident new Israeli Prime Minister Benjamin Netanyahu fully grasps the gravity of the situation and will respond accordingly.