TEHRAN, Iran — Efforts to find a diplomatic solution to Iran's disputed nuclear program appeared to get a boost Tuesday, Mar. 6 when world powers agreed to a new round of talks with Tehran, and Iran gave permission for inspectors to visit a site suspected of secret atomic work.

The two developments countered somewhat the crisis atmosphere over Iran's nuclear program, the focus of talks in Washington between President Barack Obama and Israel's visiting prime minister.

Speaking at a news conference, Obama said he saw a "window of opportunity" to use diplomacy instead of military force to resolve the dispute over Iran's nuclear program.

He said he is focused on "crippling sanctions" already imposed on Iran and on international pressure to keep Tehran from developing a nuclear weapon. Iranians need to show they are serious about resolving the crisis, he said, adding that his policy is not one of containment but of stopping Iran from acquiring a nuclear weapon. The U.S. and its allies say Iran is on a path that could lead to the production of a nuclear weapon. Iran denies that, insisting its program is for energy production and other peaceful purposes.

Speaking in Brussels, EU foreign policy chief Catherine Ashton said the five permanent members of the U.N. Security Council and Germany had agreed to a new round of nuclear talks with Iran. Previous talks have not achieved what the powers want — an end to uranium enrichment on Iranian soil. The last round ended in failure in January 2011.

Ashton said the EU hopes Iran "will now enter into a sustained process of constructive dialogue which will deliver real progress in resolving the international community's long-standing concerns on its nuclear program."

The time and venue of the new talks have not yet been set.

Britain's foreign secretary, William Hague, said the onus would "be on Iran to convince the international community that its nuclear program is exclusively peaceful."

German Foreign Minister Guido Westerwelle called for a diplomatic solution. "A nuclear-armed Iran must be prevented," he said. This week Obama warned the U.S. would use military action to protect its interests if necessary, while appealing for time for sanctions against Iran to show their affects. In his public statements during a visit to Washington, Israeli Prime Minister Benjamin Netanyahu thanked Obama for his support but did little to counter concerns that Israel might go ahead on its own with an attack on Iran. Israel considers Iran an existential threat because of its nuclear program and its references to destruction of the Jewish state.