30 July 2012US Republican presidential candidate Mitt Romney would respect an Israeli decision to use military force to stop Iran from developing a nuclear weapon, one of his aides has said.
Romney, who is in Jerusalem, is expected to pledge closer ties between the US and Israel if he is elected.
US President Barack Obama has focused on using sanctions to contain Iran's nuclear ambitions.
On Sunday morning Romney held talks with Israeli Prime Minister Benjamin Netanyahu and President Shimon Peres.
He told Peres he shared Israel's concern about the development of Iran's nuclear capabilities, saying: "The threat it would pose to Israel, the region and the world is incomparable and unacceptable."
Romney will give a speech later on Sunday near Jerusalem's Old City in which he is expected to say it is "unacceptable" for Iran to have the "capacity" to develop nuclear weapons.
"If Israel has to take action on its own, in order to stop Iran from developing the capability, the governor (Romney) would respect that decision," his foreign policy adviser Dan Senor told reporters ahead of the speech.
After his meetings with Israeli officials, he went to Jerusalem's Western Wall, one of Judaism's holy sites.
Romney will be hoping that burnishing his pro-Israel credentials will help him among key constituencies in a tight race with Obama, analysts say.
Romney says Obama has undermined Israel and supported its enemies.
The Republican presidential hopeful is also scheduled to meet Palestinian Prime Minister Salam Fayyad, though not Palestinian President Mahmoud Abbas.