Democratic White House hopeful Hillary Clinton says in case she becomes the next US president she would support Israel against Iran.

In an interview with the ABC News, when she was asked what she would do if Iran attacked Israel, she said "I want the Iranians to know that if I am the president we will attack Iran."

"In the next ten years, during which they might consider launching an attack on Israel, we would be able to totally obliterate them," she added.

Clinton's support for the regime comes as Tehran has never declared any program to launch a military attack on Israel.