Congress this week will finally hear from UN patent agency whistleblowers about years-old computer shipments to Iran that have raised questions about the world body’s compliance with international sanctions.

The Feb. 24 hearing with three former officials of the World Intellectual Property Organization (WIPO) caps a four-year battle against stonewalling bureaucrats at the Geneva-based agency. At the same time, the House Foreign Affairs Committee hearing opens another front in the congressional campaign to ensure that international pressure on Iran doesn’t let up in the wake of last year’s nuclear deal.

“With the UN wrapping up its own investigation,” Middle East panel Chairwoman Ileana Ros-Lehtinen, R-Fla., said in a statement, “this hearing will provide an added layer of oversight and accountability, as members will hear from the WIPO officials previously blocked from testifying, learn what consequences we can expect from the UN investigation, and assess future action to safeguard against potential violations of US sanctions and export controls and other breaches of US national security policy by WIPO and other UN agencies.”

The controversy dates back to April 2012, when Fox News first reported that the Geneva-based agency had shipped sophisticated US-made computers and other information technology systems to internationally sanctioned North Korea, without seeking permission from — or even informing — the UN Security Council. Three months later, Bloomberg reported that similar technology transfers had also been made to Iran.