The United States granted 180-day waivers on Iran sanctions to China, India and seven other countries on Friday in exchange for those nations cutting purchases of oil from the Islamic Republic.
U.S. President Barack Obama's administration has now renewed waivers for all 20 of Iran's major oil buyers, after granting them to Japan and 10 EU countries in September. Friday's action was the second renewal for all 20 after Obama signed the sanctions into law a year ago.
The sanctions aim to choke funding to Iran's nuclear program, which the West suspects is enriching uranium to levels that could be used in weapons. Tehran says the program is for civilian purposes.
"The United States and the international community remain committed to maintaining pressure on the Iranian regime until it fully addresses concerns about its nuclear program," Secretary of State Hillary Clinton said in a statement.
Clinton also granted waivers, known as "exceptions," on Friday to South Korea, South Africa, Turkey, Sri Lanka, Malaysia, Singapore and Taiwan.
Iran's oil exports have fallen 50 percent this year in the face of U.S. and EU sanctions.
In September and October, the latest months for which data were available, Iran's crude production fell by 1 million barrels per day, compared with the same time last year, according to the U.S. Energy Information Administration.
Clinton said Iran should take "concrete actions" to satisfy the international community through negotiations with the U.N. Security Council members plus Germany "or face increasing isolation and pressure."
China, which is Iran's top oil customer and a permanent member of the U.N. Security Council, has opposed unilateral sanctions such as those imposed by Washington.
But its oil imports from Iran are down 22 percent on the year to 426,000 bpd from January to October. Early in the year, the imports were cut as China and Iran butted heads over a contract dispute. More recently, Iranian tankers have struggled to ship even reduced volumes requested by importers.
Under the law, banks in countries that buy oil from Iran can be cut off from the U.S. financial system unless their purchases decline.
Top sanctions backers in Congress, Senators Robert Menendez, a New Jersey Democrat, and Mark Kirk, an Illinois Republican, have urged Obama to require oil importers to reduce purchases by 18 percent or more to qualify for the further waivers.
State Department officials have not forced countries to cut by specific percentages to get the waivers. But they have engaged in conversations with them about turning to alternative oil suppliers like Iraq and Saudi Arabia.
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