Former U.S. President George H.W. Bush and U.S. Ambassador William Timken cut a red ribbon to mark the opening of the $130 million diplomatic headquarters. About 4,500 people were invited to the ceremony by U.S. officials.

German Chancellor Angela Merkel recalled how the late U.S. President Ronald Reagan had once stood nearby and appealed to the Soviet Union's last communist leader: "Mr. (Mikhail) Gorbachev, open this gate! Mr. Gorbachev, tear down this wall!"

Bush credited the wall's removal with "ending the division of Europe."

While German critics have focused on the structure's bland design, U.S. critics have lambasted the project for its focus on symbolism rather than security.

"We could have built an embassy out in the woods at half the cost and twice the security," Timken said in defending the building. "We are here as a symbol of our desire to be a partner to Germany."

Henrich Boll Foundation foreign policy director Bastian Hermisson said the new embassy and its opening event should help promote diplomacy, The Christian Science Monitor reported Thursday.

"These July 4 festivals can be important -- not as receptions for the political class, but something open, where the Americans are saying, 'Hey, let's have some burgers together.' This is something we like," he said.