During a visit Sunday to Israel, the man expected to be the Republican Party nominee for U.S. president, Mitt Romney, said it is “unacceptable” for Iran to acquire a nuclear weapon.

It was during an appearance with Israeli President Shimon Peres that Romney made his statement on Iran.

“We are very concerned about the development of nuclear capacity on the part of Iran and feel it is unacceptable for Iran to become a nuclear armed nation. The threat it would pose to Israel, to the region and to the world is incomparable and unacceptable.”

The former Massachusetts governor is in the middle of a trip to Britain, Israel and Poland that analysts say is intended in part to demonstrate some expertise in foreign policy. In his public comments in Israel, he did not go as far as his foreign policy adviser Dan Senor, who told reporters that, if elected president, Romney would not try to stop Israel from attacking Iran’s nuclear sites.