The Congress on Saturday hailed the framework agreement on Iran's nuclear programme struck between it and the five permanent UN Security Council members along with Germany.
Senior party leader Anand Sharma said the understanding was of "great" significance, which would "contribute towards regional stability and also in phasing out of the financial and economic sanctions against Iran".
He said the Congress consistently believed in peaceful resolution of the contentious nuclear issue by way of diplomacy and dialogue.
"It was therefore important that Iran's right to peaceful uses of nuclear energy is recognized and respected while fully addressing international community's concern that Iran's nuclear programme remains exclusively peaceful," he said in a statement.
Describing the understanding as "reassuring", he said the Congress hoped for a "lasting solution" acceptable to all the stakeholders.
In the Swiss city of Lausanne, the US, Britain, France, Russia, China and Germany reached an understanding with Iran on April 2 that released it of all economic and financial sanctions in return of limits to its nuclear programme.