Barack Obama has told Germans that he will not allow America's massive communications surveillance capability to damage relations with their country and other close US allies.
President Obama made the pledge in a rare interview with Germany's ZDF television in an apparent move to repair the damage to America's relations with Germany and other countries following reports that the US National Security Agency had monitored communications of European citizens - even listening in on chancellor Angela Merkel's mobile phone.
Ms Merkel accused the US of a grave breach of trust after reports about her phone emerged in October and her government has been pressing for a "no spying" agreement with Washington since then.
Her centre-right party's foreign policy spokesman Philipp Missfelder said on Thursday that revelations about US spying in Germany had plunged relations with Washington to their lowest level in more than a decade.
During the 16-minute TV interview, Mr Obama acknowledged the anger in Germany and elsewhere ignited by spy revelations following the leak of documents obtained by former NSA analyst Edward Snowden to news media.
He said it would take time to restore trust, but defended US surveillance as necessary to protect America and its allies, including Germany.
Mr Obama said that before the revelations he had forged a close working relationship with Ms Merkel and that he could not allow US surveillance operations to damage that trust.
"As long as I am president of the United States, the German chancellor need not worry about that," he said, according to a simultaneous German translation as he spoke.
He said that in foreign policy issues even close partners did not share the same views but "that is no reason" to spy on private communications.
The interview was broadcast a day after Mr Obama ordered new limits on the way US intelligence accesses phone records from hundreds of millions of Americans and moved towards eventually stripping the massive data collection from the government's hands.
He also promised to curb spying on allied leaders and to extend some privacy protections to foreign citizens - demands that have special resonance in Germany because of its bitter memories of massive domestic surveillance by the Nazis and East German communists.
Interviewer Claus Kleber told the president that initial reaction in Germany towards his speech had been "sceptical, careful, many even disappointed", including those who are "normally pro-American".
Following Friday's speech, government spokesman Steffen Seibert said Germany would wait and see what happens before making a final judgment on Mr Obama's intelligence reforms.
"The government continues to expect that German law be respected on German territory, including and particularly by our close partner," Mr Seibert said.
Germany hosts more than 30,000 American troops, mostly in the south and west. The German news weekly Der Spiegel, citing Snowden documents, has reported that US diplomatic and military facilities in Germany have been used for surveillance operations in the past.