A large bipartisan slate of U.S. senators urged European Union officials to authorize the body's central bank to shut Iran out of its money transfer system.
The Feb. 25 letter to the president of the European Council, initiated by Sens. Jeanne Shaheen (D-N.H.) and Mark Kirk (R-Ill.) and signed by another 34 senators, asks the council to direct the European Central Bank to ban access by Iranian regime officials to "Target2," the bank's cross-border funds transfer system.
The senators allege that Iran uses the system to launder euros in its accounts, allowing it to alleviate tough U.S. and European sanctions aimed at forcing the regime to be more transparent about its nuclear program.
"It is critical that the U.S. and Europe present a strong, unified front with respect to Iran's nuclear program," the letter said.
Separately, Iran and major power negotiators meeting in Kazakhstan agreed Wednesday to reconvene next month in Istanbul to further discuss proposals by the major powers that would alleviate some sanctions in exchange for greater access to Iran's nuclear facilities.
The top Iranian negotiator, Saeed Jalili, said the proposals were "more realistic" than previous such offers.
Similar talks ended in failure in 2011.
Western intelligence agencies suspect Iran plans to manufacture a nuclear weapon. Iran insists its program is peaceful.