U.S. President Donald Trump was in a bullish mood as he and other global leaders in Egypt signed on Monday the first phase of the Gaza ceasefire agreement, seen as a precursor to a possible peace deal between Hamas and Israel.

“This took 3,000 years to get to this point, can you believe it? And it’s going to hold up too,” Trump said confidently as he signed the deal in front of the world’s media.

“We’ve achieved what everybody said was impossible — at long last, we have peace in the Middle East,” Trump said later during a news conference, flanked by other leaders. “Nobody thought we could ever get there, and now we’re there,” he added.

While most agree that Trump deserves credit for helping to bring an immediate end to the devastating war between Israel and Hamas — which saw the return of Israeli hostages after two years in captivity and release of almost 2,000 Palestinian prisoners and detainees — achieving a long-lasting peace is a different matter.

“At the end of the day, getting to a ceasefire was very, very important. It was important not just for Gaza and Israel, but for the whole region which has been consumed by this conflict. But it’s also the easy part,” Rob Geist Pinfold, lecturer in International Security, at King’s College London, told CNBC Tuesday.