Syria Sanctions Enhancement Act of 2013

Applies specified penalties under the International Emergency Economic Powers Act to a U.S. person that: (1) conducts investment activities in Syria; (2) exports, sells, or supplies a service from the United States to the government of Syria; (3) conducts a transaction involving petroleum or petroleum products of Syrian origin; or (4) approves, finances, or facilitates a transaction by a foreign person that would be prohibited if conducted by a U.S. person.

Applies such property and penalty requirements to contracts or other agreements entered into on or after December 1, 2013.

Amends the Iran Threat Reduction and Syria Human Rights Act of 2012 to expand the list of persons: (1) responsible for human rights abuses committed against Syrian citizens, and (2) subject to sanctions for transferring goods or technologies to Syria that are likely to be used to commit human rights abuses.

Urges the President to commence diplomatic efforts to establish a multilateral sanctions regime against Syria.

Directs the President to impose specified sanctions against a person that: (1) exported, transferred, or facilitated the transshipment of, any goods, services, technology, or other items would likely result in another person exporting, transferring, transshipping, or otherwise providing the goods, services, or technology to Syria; and (2) knew or should have known that such action would contribute materially to the government of Syria's ability to acquire or develop chemical, biological, or nuclear weapons or related technologies, or acquire or develop conventional weapons for use against the people of Syria.

Declares that this requirement shall not prohibit the United States from transporting weapons and aid to forces opposing the government of Syria.

Directs the President to impose specified sanctions against a person that: (1) sells or provides defense articles to the government of Syria; or (2) sells, leases, or provides to the government of Syria goods, services, technology, information, or support that could contribute to the government of Syria's ability to import defense articles.

Imposes additional sanctions on the transfer of nuclear technology to the government of the country having primary jurisdiction over a person subject to nuclear weapons-related sanctions under this Act.

Directs the President to impose specified sanctions against a person that knowingly provides training to the government of Syria's military or paramilitary forces.

Directs the President to impose specified sanctions on a person that knowingly sells or provides to Syria certain refined petroleum and infrastructure development-related resources goods, services, technology, or support.

Sets forth categories of sanctionable persons under this Act.

Sets forth the following sanctions: (1) prohibitions on Export-Import Bank assistance; (2) export restrictions; (3) prohibitions on loans from U.S. financial institutions; (4) prohibitions on sanctioned financial institutions; (5) procurement contract prohibitions; (6) foreign exchange prohibitions; (7) property transaction prohibitions; (8) prohibitions on investment in equity or debt; (9) U.S. entry exclusions of corporate officers, controlling shareholders, or principals of a sanctioned entity; and (10) import restrictions.

Requires: (1) a certification from each prospective federal contractor that the person, and any person owned or controlled by such person, does not engage in a sanctioned activity; and (2) the head of an executive agency, with respect to a person that has submitted a false certification, to terminate a contract with such person, or debar or suspend such person from federal contract eligibility for not more than three years.

Directs the Secretary of the Treasury to prescribe regulations to prohibit or condition the opening or maintaining in the United States of a correspondent account or a payable-through account by a foreign financial institution that knowingly: (1) facilitates the efforts of Syria, Hezbollah, or others engaged in armed conflict on behalf of the government of Syria to acquire or develop weapons of mass destruction, or to support foreign terrorist organizations or international terrorism; (2) engages in money laundering to carry out such activities; (3) facilitates efforts by the Central Bank of Syria or other Syrian financial institution to carry out such activities; or (4) facilitates a significant transaction or transactions or provides significant financial services for a person whose property or interests in property are blocked in connection with the proliferation of weapons of mass destruction, support by Syria for international terrorism, or human rights abuses by Syria.

Directs the Secretary of the Treasury to prescribe regulations to: (1) prohibit any person owned or controlled by a domestic financial institution from knowingly engaging in a transaction or transactions with or benefitting the government of Syria, Hezbollah, or any of its agents or affiliates whose property or property interests are blocked pursuant to the International Emergency Economic Powers Act; and (2) require a domestic financial institution maintaining a correspondent U.S. account or payable-through account for a foreign financial institution to establish due diligence policies to detect whether the foreign financial institution has knowingly engaged in any prohibited activity.

Sets forth related penalty requirements.

Directs the President to report to Congress every 120 days on Syria's military capabilities.

Directs the Secretary of the Treasury to report to Congress every 90 days on Syria's assets held by financial institutions.

Terminates sanctions and sanction authority under this Act when the President certifies to Congress that: (1) the government of Syria is not using weapons against the people of Syria, is not supporting international terrorist groups, is not developing or deploying surface-to-surface ballistic missiles, and is not engaging in the development, acquisition, production, transfer, or deployment of biological, chemical, or nuclear weapons; or (2) a successor government of Syria has been democratically elected, or a legitimate transitional government of Syria is in place.