London (CNN) -- Britain cut all financial ties Monday with Iran over concerns about Iran's nuclear program, the first time it has ever cut an entire country's banking sector off from British finance, the British Treasury announced. The move comes days after an International Atomic Energy Agency report highlighted new concerns about "the possible military dimensions of Iran's nuclear program," the Treasury statement said Monday. The IAEA's governors approved a resolution last week expressing "deep and increasing concern about the unresolved issues regarding the Iranian nuclear program. Iran insists its nuclear program is peaceful and has called the U.N. watchdog's report "unbalanced" and "politically motivated."
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British companies must end all banking ties to Iran by Monday afternoon
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Secretary of State Hillary Clinton to outline new steps U.S. is taking to pressure Iran
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The IAEA raises "deep and increasing concern" regarding the Iran's nuclear program
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Iran calls U.N. watchdog's report "unbalanced" and "politically motivated"
"@placeholder banks play a crucial role in providing financial services to individuals and entities within Iran's nuclear and ballistic missile programs, as companies carrying out proliferation activities require banking services."