Ron Dermer has been appointed Israel’s next ambassador to the United States, the Prime Minister’s Office confirmed on Tuesday, ending months of speculation over who would gain the coveted role.

“Ron Dermer has all the qualities necessary to successfully fill this important post,” Prime Minister Benjamin Netanyahu said. “I have known him for many years and I know that Ron will faithfully represent the state of Israel in the capital of our greatest ally — the USA. On behalf of the citizens of Israel, I wish him great success.”

US-born Dermer, 42, a key adviser to Netanyahu, will take over the key post from another US-born political appointee, Michael Oren, who has held the job for the past four years.

“I wish to express my warmest congratulations to Ron Dermer who has been appointed by PM Netanyahu as Israel’s ambassador-designate to the US,” outgoing ambassador Oren said Tuesday via Twitter. “As Ron’s close friend and long-time colleague, I know that he’s uniquely qualified and is deeply committed to the historic US-Israel alliance.”

Dermer reportedly met in recent days with US Ambassador to Israel Dan Shapiro to discuss his appointment.

Dermer, who immigrated to Israel from Florida in 1998, has served under Netanyahu since 2009 as senior adviser in the Prime Minister’s Bureau, where he acted as liaison to the White House.

From 2005 to 2008, he served as economic affairs minister to the Israeli Embassy in Washington, a position which required him to give up his US citizenship.

Dermer is a graduate of the Wharton School of Business at the University of Pennsylvania and holds a master’s degree in philosophy, politics and economics from Oxford. In 1995, while still a student at Oxford, he helped manage Natan Sharansky’s Yisrael b’Aliyah party’s Knesset campaign.

He later became an adviser to Sharansky and co-wrote Sharansky’s bestselling foreign-policy treatise, “The Case for Democracy,” before moving on to work for Netanyahu.

“Ron reminds us what Israel is all about,” Sharansky told The Times of Israel on Tuesday. “He came as a new immigrant, a young man … Now he’s going back to the United States as Israel’s ambassador. Ron has an extremely deep sense of the foundation of the connection between Israel and America, our mutual values. He wrote about it, he studied it, he lives it… Ron will be extremely important to Washington and the White House because they know he’s very close to the prime minister, that speaking to him is like speaking to Netanyahu; that’s a very rare thing,” he added.

Dermer’s father, lawyer Jay Dermer, served in the 1960s as the mayor of Miami Beach, Florida; and Dermer’s brother, David Dermer, later also served as Miami Beach mayor. Dermer’s mother was born in Mandatory Palestine and later emigrated with her family to the US.

A June Channel 10 report noted that Dermer, who has long been groomed for the job, saw his prospects nosedive due to his perceived support for Republican candidate Mitt Romney in the last US presidential election.

However, the report said, he has since improved his ties with key Obama administration figures, notably Secretary of State John Kerry, paving the way for his appointment.

Tablet magazine feature last year said Dermer “has done more to shape Israel’s relationship with the United States, its Arab neighbors, and the Palestinians over the past few years than any man aside from the prime minister himself.”

Married with five children, Dermer is an engaging and effective advocate for Netanyahu’s worldview, one insider said.

“I welcome Ron Dermer’s appointment as the new Israeli ambassador to the United States,” Deputy Foreign Minister Ze’ev Elkin said on Tuesday. “Dermer will be an excellent ambassador. He has a deep understanding of America and, as a former diplomatic adviser to the prime minister, is familiar with the most sensitive issues of Israeli foreign policy in recent years. His appointment demonstrates the level of intimacy in our relationship with the United States, and the importance that the prime minister ascribes to this relationship,” he added.

The pro-Israel American-Israel Public Affairs Committee (AIPAC) also welcomed Dermer’s appointment.

“Mr. Dermer has a deep understanding of the critical value of the US-Israel relationship and the importance of further strengthening the alliance between these two democratic allies,” the group said in a statement. “We also express our gratitude to Ambassador Oren for his service over the past four years as he worked tirelessly and effectively to bolster the bond between the United States and Israel.”

JTA contributed to this report.