WASHINGTON — President Obama recently signed enhanced Iran sanctions into law.

Representatives of a number of pro-Israel groups, as well as the congressional leadership of both parties, were invited to witness the signing of the sanctions. They target third parties that deal with Iran’s energy and finance sectors, as well as human rights abusers.

“For years, the Iranian government has violated its commitments, defied United Nations Security Council resolutions and forged ahead with its nuclear program — all while supporting terrorist groups and suppressing the aspirations of the Iranian people,” Obama said.

He placed the sanctions in the context of international efforts to ramp up Iran’s isolation until it makes transparent its nuclear program, including new U.N. Security Council resolutions issued last month.

“Consistent with the Security Council mandate, this legislation strengthens existing sanctions, authorizes new ones and supports our multilateral diplomatic strategy to address Iran’s nuclear programs,” he said.

“It makes it harder for the Iranian government to purchase refined petroleum and the goods, services and materials to modernize Iran’s oil and natural gas sector.

“It makes it harder for the Revolutionary Guards and banks that support Iran’s nuclear programs and terrorism to engage in international finance. It says to companies seeking procurement contracts with the United States government [that] if you want to do business with us, you first have to certify that you’re not doing prohibited business with Iran.”

The sanctions were approved last week in Congress, with overwhelming majorities in both Houses.