NEW: Der Spiegel: U.S. spied on Merkel for more than 10 years, at least until June NEW: NSC doesn't comment on claim, says U.S gets intelligence like other nations (CNN) -- Germany is sending senior intelligence officials to Washington, a Foreign Ministry spokesman said Saturday, amid outrage over claims the U.S. National Security Agency monitored German Chancellor Angela Merkel's cell phone. The trip comes amid a series of reports that have challenged relations between the two long-time allies. The latest is a story in the German magazine Der Spiegel that -- citing a secret U.S. intelligence file -- claimed Merkel's phone had been monitored for more than 10 years, stretching back before her current post. The same database indicated the United States was spying on many others in Berlin's political district, at least up to when U.S. President Barack Obama visited Berlin this year, Der Spiegel reported. Asked about these claims, U.S. National Security Council spokeswoman Caitlin Hayden said her agency does not "comment publicly on every specific intelligence activity." "And, as a matter of policy, we have made clear that the United States gathers foreign intelligence of the type gathered by all nations," said Hayden, echoing comments she and others have made in recent days. Still, it remains to be seen if citizens and leaders in Europe will accept such explanations -- and whether recent efforts by the Obama administration to address their concerns will be successful. Spokesman: U.S.-German talks ongoing for months The German government's deputy spokesman said Friday that its officials heading to Washington would seek to push forward talks with the White House and the NSA as they seek more information about the alleged U.S. spying. The United States has been in talks with German intelligence officials for the past several months, and leaders of both countries have agreed to increase cooperation, said Hayden of the National Security Council. "We understand that German officials plan to travel to Washington in coming weeks, and the U.S. government looks forward to meeting with them," she said. Germany and Brazil are also drafting a U.N. resolution regarding the protection of privacy in electronic communication, according to the German foreign ministry spokesman said. Diplomats from those two countries met Thursday to discuss the possible U.N. resolution, government officials in Brazil said. It is still at a very early stage, so we don't know when it will be presented or if other countries will join," the German spokesman said. U.S. relations have soured with Brazil over reports that the United States spied on President Dilma Rousseff and her advisers. Obama has directed the government to review its surveillance capabilities, including with regard to its foreign partners, she said. CNN's Chloe Sommers and Frederik Pleitgen contributed to this report.