Iran struck a historic agreement with the U.S. and five other world powers on Sunday to accept strict restraints on its nuclear program in exchange for eased sanctions.

The agreement, which came 10 years after Iran's nuclear ambitions first sparked global concerns, is being hailed as an important first step in resolving the dispute.

Korean companies have pricked up their ears since eased sanctions herald increased business opportunities as well as more imports of oil from Iran.

Trade between Korea and Iran has shrunk since tougher international sanctions came into force. Bilateral trade stood at US$17.4 billion in 2011 but fell to $14.8 billion last year. In the first 10 months of this year, Korean exports to Iran fell 30 percent on-year to $3.8 billion.

The Korea Institute for Industrial Economics and Trade projects Korean shipments of cars, automotive parts and other consumer goods to Iran will increase to pre-sanctions levels. Korean fir ms will be able to cut transportation costs and boost exports as shipping routes to Iran reopen.

Korean builders and plant makers are also expected to benefit. Until the mid-2000s, Iran was among the top five overseas markets for Korean construction firms, but orders ceased following international sanctions since 2009.

