US Defense Secretary Robert Gates heads to Israel Sunday as part of the US diplomatic efforts to narrow differences between the two countries over Jewish settlements on Palestinian land and coordinate their common stance on Iran's nuclear issue.

Gates is due to meet his Israeli counterpart Defense Minister Ehud Barak on Monday, before holding talks with Prime Minister Benjamin Netanyahu,.

Settlement rift

Since US President Barack Obama took office, his administration has repeatedly demanded that Israel halt all settlement activity in the occupied West Bank including annexed East Jerusalem.

Israeli Prime Minister Netanyahu has said he would not build any new settlements but construction must be permitted inside existing settlements to accommodate what he calls "natural growth" in their populations.

"We do recognize that we have a different view on the settlements between Israel and the United States. This is not new," said Israel's Deputy Foreign Minister Danny Ayalon in an interview with Xinhua.

At a seminar last week organized by the Institute for National Security Studies (INSS), a Tel Aviv-based think tank, some Israeli experts have expressed doubts whether the Obama administration has thorough understanding of the Mideast-related issues.

In the view of one senior researcher at the seminar, the United States singled out the settlement issue for breakthrough in peace talks because they take it as an easier target, but he asked "do they really understand this issue?"

A latest survey found that only 38 percent of Israelis have favorable views on Obama, compared with the findings of a 2007 poll that showed 73 percent of Israelis think Obama's predecessor George W. Bush was friendly to Israel.

Nevertheless, Ayalon, who used to serve as Israeli ambassador to the United States, was optimistic about the prospect of bilateral ties.

"The friendly relations and the common interests of the two countries will help resolve the current differences, " he told Xinhua.

Disparity on Iran's nuclear issue

The Obama administration, bent on peruading Iran to give up its nuclear program via engagement policy, seemed discouraged by the outcome of Iran's presidential election.

Iran's president-elect Mahmoud Ahmadinejad reiterated that on the issue of "utilizing nuclear power for peaceful purpose" his country would never bow to pressures by Western powers led by the United States.

Curbing Iran's possible nuclear threat involves the common interest of the United States and Israel, but the two countries have taken different approaches to that end.