Afghanistan, June 3 -- U.S. President Donald Trump is seeking written commitments from Iran on its nuclear program as part of an initial understanding being negotiated between Washington and Tehran, according to media reports.

ABC News reported, citing sources familiar with the discussions, that Iranian negotiators have provided verbal assurances that Tehran would ultimately accept some restrictions related to its nuclear activities. Trump, however, has reportedly insisted that verbal guarantees are insufficient.

According to the report, Trump told advisers during a White House meeting that any agreement must include written commitments before the United States can move forward.

The negotiations are focused on a preliminary framework tha...