Israeli Prime Minister Benjamin Netanyahu congratulated U.S. President-elect Joe Biden on Sunday, hailing a strong alliance that could be burdened by differences over policy on Iran and the Palestinians. “Congratulations @JoeBiden and @KamalaHarris. Joe, we’ve had a long & warm personal relationship for nearly 40 years, and I know you as a great friend of Israel. I look forward to working with both of you to further strengthen the special alliance between the U.S. and Israel,” Netanyahu said on his Twitter account, which still carries a photograph of him and incumbent U.S. President Donald Trump at its head. Having been in lockstep with Trump for four years, Netanyahu will likely be challenged by any departure by Biden from Trump’s tough policy on Iran and toward the Palestinians. Biden has pledged to restore U.S. involvement in the 2015 Iran nuclear deal - which Trump had pulled out of - and a likely opposition by the White House to Israeli settlement of occupied land where Palestinians seek statehood. Netanyahu thanked Trump in a subsequent tweet: “Thank you @realDonaldTrump for the friendship you have shown the state of Israel and me personally, for recognizing Jerusalem and the Golan, for standing up to Iran, for the historic peace accords and for bringing the American-Israeli alliance to unprecedented heights.” Netanyahu’s message came hours after many world leaders had already congratulated Democrat Biden, even as Trump refused to concede and pressed ahead with legal fights against the outcome. A spokesman for Netanyahu did not respond to a request for comment on the relative delay. Dani Dayan, Israel’s former consul to New York said Netanyahu’s slowed response was a precautionary move. “There is a president in the White House who has not yet acknowledged his defeat and whose whims definitely play a major role in his decision making process and he will be sitting in the White House for another two and a half months,” Dayan told Army Radio. The right-wing Netanyahu’s particularly close ties with Trump followed an acrimonious relationship with his predecessor Barack Obama, which some critics have said had alienated Democrats and compromised U.S. bipartisan support for Israel. Michael Oren, Netanyahu’s ambassador to Washington when Obama was president, predicted warm ties with Biden. “They will have disagreements over the peace process. They will have disagreements certainly over the Iran nuclear deal but I think their friendship is solid.” Israel’s stock market responded positively to Biden’s win. Both the blue-chip Tel Aviv 35 index and the broader TA-125 were up about 0.3% in morning trade. Still, among Israelis, Trump has won overwhelming popularity and many may be sad to see him go. “I think the problem is that Biden will not be as tough or as strong as Donald Trump,” said Aaron Morali, a student from Tel Aviv. “He made it hard for the Iranian people to have a nuclear plan but I think with Biden they have someone very easy and I am very, very scared of what will happen.”