WASHINGTON, D.C. — Though it took former President Trump a mere two days after his inauguration to call Israel’s Benjamin Netanyahu, President Biden is yet to do so.

Biden has called many world leaders in the first three weeks of his presidency, including leaders of Russia, China, France, Japan and more.

Israeli diplomats and foreign policy experts are now speculating that Netanyahu has cause for concern that he is getting the cold shoulder from Biden because of the Israeli PM’s past cozy relationship with the Trump administration.

“It’s a clear sign of displeasure from President Biden with the fact that Prime Minister Netanyahu was perceived in Washington for the last 12 years as almost a card-carrying member of the Republican Party,” Dani Dayan, a former Israel consul-general in New York, told NBC News.

NBC also reported that Danny Danon, Israel’s former ambassador to the United Nations and a member of Netanyahu’s Likud party, asked Biden over Twitter, “Might it now be time to call the leader of Israel, the closest ally of the U.S.?” before typing out a phone number for Netanyahu’s office.

“Is Biden ghosting Netanyahu?” asked one conservative Israeli columnist.

But Netanyahu himself has insisted that the U.S.-Israeli relationship remains strong.

“(Biden) is making calls to world leaders according to the order he sees fit,” Netanyahu said. “The Israel-U.S. alliance is strong and so is our friendship of almost 40 years, though we may not agree on everything.”

Biden, who has referred to himself as a Zionist in the past, and has defended U.S.’ $38 billion aid deal with the country, has always been a supporter of the country and has enjoyed a friendly relationship with its right-wing leader.

He has expressed dismay in the past over continued settlement building over Palestinian land, as a deterrent to a two-state solution for the conflict in the region, especially during a 2010 visit to the region when he was vice president.

The White House has assured that Netanyahu is on the list for future calls by the newly-elected U.S. president, but no date has provided as of yet.

Israel and the Biden administration may see some bumps in the road in their relationship going forward. Biden has pushed for a return to a nuclear deal with Iran, something Netanyahu was sharply critical of when it was enacted during the Obama administration.

Netanyahu has also pushed back against Biden not completely adhering to Trump’s recognition of Israel’s sovereignty over the Golan Heights.

The White House has indicated that Biden will be contact with Netanyahu soon enough, and one of the most controversial moves by Trump will remain in place: The U.S. embassy will remain in Jerusalem. Biden has promised a renewal of diplomatic engagement with Palestinian leaders and a resumption of aid to Palestine.