The European Union and the United States agreed on Monday that addressing global warming is a pressing issue, with President George W. Bush acknowledging the necessity of convincing Russia about the importance of a missile shield in Europe. During a White House summit, Bush, German Chancellor Angela Merkel, and European Commission President Jose Manuel Barroso reaffirmed their commitment to finalizing a global trade agreement as part of the Doha round of talks. They continued to urge Iran to abandon its nuclear weapons program, despite Tehran's refusal to halt uranium enrichment. Merkel, on her first visit to Washington since assuming the EU presidency, emphasized the importance of addressing global climate change ahead of the upcoming Group of Eight summit in Germany in June. During a press conference held together in the Rose Garden, the European representatives expressed satisfaction with the progress made on the issue, even though no specific actions were decided upon for the EU and the United States to tackle the problem together. Barroso stated that he was pleased with the progress made during the meeting, highlighting the shared understanding that there is a significant global threat posed by emissions and the importance of working together to reduce them. Bush, who was criticized for being slow to acknowledge climate change as a problem, emphasized that any agreement between the United States and Europe would not have a significant impact unless developing countries like China were included. He pointed out that even if the United States completely stopped emitting greenhouse gases, China could easily surpass that level of emissions in a short period of time. In response, Merkel argued that it is essential for developed countries with advanced technologies to take the lead in reducing carbon emissions. She stated that without action from developed countries, it would be difficult to convince others to follow suit and global CO2 emissions would not decrease. The leaders of the US and EU met amidst Russian criticism of US plans to deploy a missile shield in Eastern Europe. Russian President Vladimir Putin vowed to take 'appropriate measures' to counter the system. President Bush mentioned that German Chancellor Angela Merkel had previously raised concerns about the missile shield and suggested that he should explain his vision to Putin. In response, Bush sent Defense Secretary Robert Gates to Moscow to offer Russia the opportunity to be involved in the shield, which is intended to counter terrorist threats rather than revive the Cold War. Bush emphasized the importance of starting a dialogue to clarify intentions and show Russia that the US is not an antagonistic force but a friendly one.