WASHINGTON – A U.S. Treasury official responsible for enacting the U.S. President Donald Trump administration's sanctions policy is resigning, at a time when the administration is reconsidering its approach towards Iran.

Sigal Mandelker, the undersecretary for terrorism and financial intelligence at the Treasury Department, will leave the administration within weeks, according to an official statement released Wednesday.

Mandelker joined the Trump administration in 2017, having previously worked for the Department of Justice under former President George W. Bush.

The official explanation for her departure is a return to the private sector. Treasury Secretary Steven Mnuchin said that Mandelker had approached him over the summer about her desire to leave.

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Mandelker played a key role in the administration's policy of heavily sanctioning Iran, as part of Trump's "maximum pressure" approach to the country.

In recent weeks, indications have arisen that Trump is seeking to end this policy in favor of direct negotiations with Iran. Negotiations almost began last week at the UN General Assembly, but Iranian President Hassan Rohani refused to meet or speak with Trump before the United States would agree to some sanctions relief.

Last month, in the run-up to the Israeli election, Prime Minister Benjamin Netanyahu told reporters that Mandelker spoke with him and assured him that despite Trump's attempts to turn over a new leaf with Iran, the pressure on the Islamic Republic would continue.

Netanyahu evoked that conversation in response to media inquiries about Trump's firing of former National Security Adviser John Bolton, who was known for his hawkish line against Iran.

It was not immediately clear on Wednesday what impact Mandelker's departure will have on the United States's attempts to open negotiations with Iran, and on the continuation of the sanctions already in place.

Reuters contributed to this report.