President George W Bush will host German Chancellor Angela Merkel at his Texas ranch in an effort to demonstrate unity on Iran despite Tehran's defiance on its nuclear program. The invitation to Crawford, Texas, is meant to signify a close relationship, and Merkel will spend two days at the ranch where they will engage in discussions on various global issues, potentially going hiking as well. White House spokeswoman Dana Perino stated that the ranch provides a great setting for both a social visit and in-depth conversations. Merkel will be the second European leader this week to receive special treatment from Bush, following French President Nicolas Sarkozy who recently visited Mount Vernon, the home of George Washington. As his time in office winds down, Bush remains committed to putting pressure on Iran regarding its nuclear activities. Iran has rejected UN demands to stop nuclear activities that could be used for both civilian and military purposes. President Mahmoud Ahmadinejad insists that Iran's nuclear program is not negotiable and reveals that there are 3,000 centrifuges in the Natanz plant. While German companies continue to do business with Iran, the United States is taking a firmer stance against Tehran. The White House National Security Council spokesperson, Gordon Johndroe, has stated that there is overall agreement on strategy, but some minor differences in tactics. Earlier this week, Merkel announced that Germany would back stricter UN sanctions against Iran if Tehran did not address concerns about its nuclear program. Bush has also criticized Iran, mentioning the possibility of World War Three if they obtain a nuclear weapon, causing concern among European allies. The Bush administration claims to be committed to diplomacy but has not ruled out any options. Perino mentioned that the two leaders would discuss working together on diplomatic efforts to convince Iran to stop uranium reprocessing and enrichment, as well as other issues such as Afghanistan, the Middle East, Iraq, climate change, and economic matters like the Doha trade round. A high-ranking official from Germany, who requested to remain anonymous, stated that Merkel and Sarkozy had decided to present a united stance on Iran, the Middle East peace process, and climate change when speaking with Bush. It is anticipated that Britain, China, France, Germany, Russia, and the United States will convene this month to review reports from the International Atomic Energy Agency regarding Iran's adherence to international requirements. According to Daniel Benjamin, a researcher at the Brookings Institution, relations between the U.S. and Germany have gotten better since Merkel replaced Gerhard Schroeder.