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WASHINGTON, Sept 20 (Reuters) - U.S. President Barack Obama will tell Iran the "door is open" to better relations with the international community, if it can demonstrate the peaceful intent of its nuclear program, the White House said on Monday.
With tough new U.N. sanctions in place, Obama will use his address to the United Nations General Assembly this week to stress to Iran the cost of its uranium enrichment program will escalate, if it fails to meet its international obligations.
"The door is open to them having a better relationship with the United States and with the international community," White House deputy national security adviser Ben Rhodes said.
"However, in order to walk through that door, Iran is going to have to demonstrate its commitment to show its peaceful intent around its nuclear program, and meet its obligations to the international community," he told reporters in a briefing.
Obama will address the United Nations General Assembly on Thursday in New York.
The U.N. Security Council, along with the United States and the European Union, have imposed tougher sanctions on Iran, which has defied international calls for it to halt uranium enrichment.
Iran says it needs the enriched uranium for the peaceful generation of electricity, but the United States and its allies, including Israel, fear Tehran's nuclear program is a cover to build an atomic bomb.
"The cost that Iran is facing has been greater than it was expecting with regard to sanctions," Rhodes said.
"The president will want to underscore, and continue to underscore, that this is a dual-track approach," he said in a conference call with reporters. "The U.N. is a useful forum to underscore that point, because our case has always been that this is not a bilateral irritant," he said.
Reporting by Alister Bull; Editing by Stacey Joyce