Story highlights Negotiators have reached a landmark deal over Iran's nuclear program

China sees economic benefits in Iran ties, authors say

Elizabeth Rosenberg is director of the Energy, Economics and Security Program at the Center for a New American Security, and Alexander Sullivan is an associate fellow in the center's Asia-Pacific Security Program. The views expressed are their own.

(CNN) As members of Congress debate whether to back the deal over Iran's nuclear program, one source of support seems guaranteed -- China. It's one of the biggest winners in the agreement, with the lifting of sanctions as Iran pulls back key elements of its enrichment program set to allow Beijing to deepen its historic partnership with Tehran. While China is undoubtedly eyeing the potential economic benefits, Beijing also likely sees an opportunity to challenge U.S. influence in the Middle East.

China has been an important critic of Iran's nuclear weapons ambitions and a supporter of nuclear diplomacy. It is therefore likely to hold ranks with the United States and other international partners during the hard work and political turbulence involved in implementing the accord. And if Iran cheats, Beijing can be relied upon to at least join in a strong statement of condemnation -- and may go along with the reimposition of sanctions on Iran.

But China also sees an important strategic opportunity in a renewed relationship with Iran, and can be expected to expand its traditional friendship in four key areas: infrastructure development, energy, limited regional security cooperation and political cooperation to dilute U.S. influence in the region.

First, through its "One Belt, One Road" initiative, China aims to link itself with Eurasia and the Middle East through trillions of dollars in infrastructure investment. Sanctions-scarred Iran is in desperate need of new infrastructure and is keen to expand the flow of people and commerce across its borders.

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