(a) In general
Except as provided in this section, the President shall prohibit the opening, and prohibit or impose strict conditions on the maintaining, in the United States of a correspondent account or a payable-through account by a foreign financial institution that the President determines has, on or after the date that is 180 days after January 2, 2013, knowingly facilitated a significant financial transaction on behalf of any Iranian person included on the list of specially designated nationals and blocked persons maintained by the Office of Foreign Assets Control of the Department of the Treasury (other than an Iranian financial institution described in subsection (b)).

(b) Iranian financial institutions described
An Iranian financial institution described in this subsection is an Iranian financial institution that has not been designated for the imposition of sanctions in connection with—

(1) Iran's proliferation of weapons of mass destruction or delivery systems for weapons of mass destruction;

(2) Iran's support for international terrorism; or

(3) Iran's abuses of human rights.

(c) Humanitarian exception
The President may not impose sanctions under subsection (a) with respect to any person for conducting or facilitating a transaction for the sale of agricultural commodities, food, medicine, or medical devices to Iran or for the provision of humanitarian assistance to the people of Iran.

(d) Applicability of sanctions to petroleum and petroleum products

(1) In general
Except as provided in paragraph (2), subsection (a) shall apply with respect to a financial transaction for the purchase of petroleum or petroleum products from Iran only if, at the time of the transaction, a determination of the President under section 8513a(d)(4)(B) of this title that the price and supply of petroleum and petroleum products produced in countries other than Iran is sufficient to permit purchasers of petroleum and petroleum products from Iran to reduce significantly their purchases from Iran is in effect.

(2) Exception for certain countries

(A) In general
Subsection (a) shall not apply with respect to a financial transaction described in subparagraph (B) conducted or facilitated by a foreign financial institution if, at the time of the transaction, the exception under section 8513a(d)(4)(D)(i) of this title applies to the country with primary jurisdiction over the foreign financial institution.

(B) Financial transactions described
A financial transaction conducted or facilitated by a foreign financial institution is described in this subparagraph if—

(i) the financial transaction is only for trade in goods or services—

(I) not otherwise subject to sanctions under the law of the United States; and

(II) between the country with primary jurisdiction over the foreign financial institution and Iran; and

(ii) any funds owed to Iran as a result of such trade are credited to an account located in the country with primary jurisdiction over the foreign financial institution.

(e) Applicability of sanctions to natural gas
Subsection (a) shall apply to a foreign financial institution that conducts or facilitates a financial transaction for the sale, supply, or transfer to or from Iran of natural gas unless—

(1) the financial transaction is only for trade in goods or services—

(A) not otherwise subject to sanctions under the law of the United States; and

(B) between the country with primary jurisdiction over the foreign financial institution and Iran; and

(2) any funds owed to Iran as a result of such trade are credited to an account located in the country with primary jurisdiction over the foreign financial institution.

(f) Waiver

(1) In general
The President may waive the imposition of sanctions under subsection (a) for a period of not more than 180 days, and may renew that waiver for additional periods of not more than 180 days, if the President—

(A) determines that such a waiver is vital to the national security of the United States; and

(B) submits to the appropriate congressional committees a report providing a justification for the waiver.

(2) Form of report
Each report submitted under paragraph (1)(B) shall be submitted in unclassified form, but may include a classified annex.