OCCUPIED JERUSALEM – The Vice Chairman of the US Joint Chiefs of Staff, Admiral James Winnefeld, is on a secret visit to Israel as tensions rise over Iran's nuclear progress, Israel's army radio reported Thursday. The Israeli military itself refused to confirm the report, which said Winnefeld was in the country at the invitation of his counterpart, Deputy Chief of Staff Major General Yair Naveh. Winnefeld visited Israel's defense minister in a display of alliance after the two countries expressed differences over Iran. He smiled broadly, exchanging pleasantries with Ehud Barak in his office in Tel Aviv. The ministry gave no details about the visit. It comes after General Martin Dempsey, chairman of the Joint Chiefs of Staff, dismayed Israeli officials by saying that Washington did not want to be “complicit” in an Israeli attack on Iran. Dempsey's comments were seen as a rebuke to Israel stepping up threats of making a unilateral strike against Iran's nuclear facilities before the US presidential election on Nov. 6. Washington has urged Israel to hold fire to give economic sanctions and diplomacy more time to curb Iran's uranium enrichment, which Tehran says is for peaceful purposes. Israel fears Iran is pursuing nuclear weapons capability - something it considers a potential threat to the country's existence. The US Embassy in Tel Aviv had no comment on Winnefeld's visit, which Israeli Army Radio said began several days ago and included an inspection of Israel's Iron Dome rocket interception system, jointly funded with the United States. Next week, another senior US military official is due in Israel, the Ynet news website reported. Lieutenant General Craig Franklin, currently the commander of the US Third Air Force, is to visit ahead of a joint military drill between the two armies which is due to take place next month, Ynet said. – Agencies