After a visit to the Western Wall and its tunnels on Sunday, U.S. National Security Adviser John Bolton met with  Israeli Prime Minister Benjamin Netanyahu to discuss regional and security issues at the prime minister’s residence, meetings that were condemned by Palestinian Authority officials.

On his tour in Jerusalem, Bolton was accompanied by U.S. Ambassador to Israel David Friedman, Israeli Ambassador to the United States Ron Dermer and Israeli national security adviser Meir Ben-Shabbat.

The group participated in a tour of the ancient historic tunnels underneath the Western Wall plaza, led by chairman of the Western Wall Heritage Foundation Soli Eliav, and saw a virtual reconstruction of the Holy Temple, which once stood on the site under the reigns of King Solomon and again under the prophet Ezra, and were completed by Herod the Great.

Foreign dignitaries are very rarely accompanied by Israeli officials on tours to the Western Wall tunnels due to the perception that they are giving official legitimacy to Israel’s sovereignty over the area. In the guestbook following his tour, Bolton wrote: “This is a great accomplishment to uncover all of this history, from the very start of our common civilization.”

In May 2017, U.S. President Donald Trump became the first sitting U.S. president to visit the Western Wall and six months later officially recognized Jerusalem as the capital of Israel, moving the U.S. embassy from Tel Aviv to Jerusalem in a ceremony attended by high-level government officials from the United States and Israel.

On Dec. 6, Netanyahu joined Friedman for a Western Wall visit in celebration of the one-year anniversary of the Trump administration’s official recognition of Jerusalem—the first time an Israeli prime minister joined a senior U.S. official at the Jewish religious site.

Prior to Bolton’s arrival, Netanyahu said he would discuss with Bolton “efforts to stop the Iranian aggression in our region, the situation in Syria following President Trump’s decision [to withdraw U.S. troops from Syria] and also following the conversation I had Friday with [Russia’s] President [Vladimir] Putin,” and said Israel would “continue to act against the military entrenchment of Iran in Syria, including during these days, and we will act against any player that will harm or try to harm Israel’s security.”

Bolton reportedly told Netanyahu that the U.S. withdrawal, rather than a time-sensitive pullout, would be contingent on the neutralization of the threat of ISIS in the country, and a guarantee by Turkey to the Kurds that fighters allied with the United States would not be threatened.

Saeb Erekat, the secretary-general of the Palestine Liberation Organization, took to Twitter to denounce the visit, arguing that it undermines international law and will “only lead to lawlessness.”

He also affirmed America’s support for continued Israeli targeting of Iranian military entrenchment in Syria.

A New York Times report said Trump would slow the U.S. troop withdrawal over a period of approximately four months, at the behest of Israel.

Netanyahu issued a statement thanking Bolton for his visit, saying it gave Israel “an opportunity to thank the Trump administration for the extraordinary support you’ve shown Israel” by reimposing sanctions on Iran, recognizing Jerusalem and supporting Israel at the United Nations, and said he intended to take Bolton to the Golan Heights in Israel’s north, to show him “why it’s important that all countries recognize Israel’s sovereignty over the Golan Heights.”

“Welcome, friend,” he concluded.

The visit was blasted by senior Palestinian Authority official Saeb Erekat, who took to Twitter to say that the “behavior” of visiting the Western Wall and its tunnels “will not change the fact that East Jerusalem is occupied territory and the capital of the state of Palestine.”