WASHINGTON - The leaders of Group of Eight (G8) major industrial nations said on Saturday that they remain united in their "grave concern" over Iran's disputed nuclear program, while urging Tehran to address such concern without delay.

"We remain united in our grave concern over Iran's nuclear program. We call on Iran to comply with all of its obligations under relevant UNSC (United Nations Security Council) resolutions and requirements of the International Atomic Energy Agency's (IAEA) Board of Governors," the G8 leaders said in a declaration issued after their summit at the Camp David, the US presidential retreat in the state of Maryland.

The G8 leaders urged Iran "to continuously comply with its obligations under the Nuclear Non-Proliferation Treaty, including its safeguards obligations," the declaration said.

They also demanded Iran "address without delay" all outstanding issues related to its nuclear program, such as questions concerning possible military dimensions, while expressing the desire for "a peaceful and negotiated solution to concerns over Iran's nuclear program."