In a joint press conference with Barack Obama in France on Saturday, French President Nicholas Sarkozy joined the US president in calling on Israel to stop building settlements in the West Bank. However, Israeli officials told Israel Radio they expect Prime Minister Binyamin Netanayhu will insist on continued settlement construction to accommodate natural growth. Obama and Sarkozy went on to warn Iran and North Korea on their nuclear programs. On Iran, the leaders again mutually called for the Islamic Republic not to develop a nuclear weapons program. The US president reaffirmed that there must be "tough diplomacy" with Teheran on the nuclear issue. Sarkozy also reiterated criticism over Iranian President Mahmoud Ahmadinejad denial of the Holocaust, and said that he worries about "insane statements" by the Iranian leader. On North Korea, the US president indicated that Pyongyang has tested the limits of patient diplomacy calculated to persuade the communist nation to get rid of its nuclear weapons. While stating that he prefers to take a diplomatic approach, Obama said the recent nuclear test and missile launches by the North Koreans were provocative. In order to continue on the diplomatic path, the North Koreans must respond in what Obama called "a serious way." He said no one should assume that the United States will continue on its current course if the North Koreans repeatedly take actions that the US considers to be destabilizing and threatening.