Pro-Israel Americans should not trust President Obama when he says he stands by the Jewish state, American Jewish casino mogul Sheldon Adelson wrote in an Op-Ed for the JNS news service.

“Time and again President Obama has signaled a lack of sympathy - or even outright hostility - toward Israel,” wrote Adelson, responding to Israeli-American businessman Haim Saban, who recently praised Barack Obama’s Israel policy in a New York Times Op-Ed.

Saban wrote that even though Obama “could have done a better job” with his Israel policy, his commitment for Israel’s security cannot be disputed, quoting Israeli national security officials as saying that the “strategic relationship between the U.S. and Israel has never been stronger than under President Obama.”

To support him claims, Adelson recalled the open microphone incident, during which Obama was heard agreeing with the then French President Nikola Sarkozy after the latter told him that he “can’t bear” Prime Minister Benjamin Netanyahu.

Adelson also made mention of the fact Obama did not meet the Israeli prime minister when he was visiting New York for the UN General Assembly last month. Adelson quoted a former State Department spokesman saying that there exists “serious differences” between Israeli and U.S. security interests.

These examples, according to Adelson, call Obama’s public commitment to stand by Israel into question, as do the president’s “anti-Israel friends and mentors.”

As for Obama’s commitment to Israel’s secutiry, the Jewish billionaire, owner of the Israeli free-distributed newspaper Yisrael Hayom, said the president cannot take credit for the record amount U.S. military aid, saying these are past commitments made by previous administrations. Also, Adelson argues, Obama should not be commended for imposing sanctions on Iran since he received bipartisan congressional support, adding later that the sanctions “contain loopholes… They won’t stop Iran’s nuclear program.”

If Obaema would win a second term, the president “won’t have fears of electoral accountability and will act upon his true feelings toward Israel,” wrote Adelson.

“For Obama, the issue is only political; for Israel, it’s existential - a matter of survival,” he said.

Adelson, 79, has pledged to donate up to $100 million to support former Governor Mitt Romney’s candidacy in the upcoming U.S. elections.

Adelson is considered a close friend of Netanyahu. Israel's prime minister has publicly denied having any preference as to who wins the U.S. elections.