What Iranian officials have said about the terms of the agreement differ from US descriptions.

• Potential agreement: US President Donald Trump says an agreement with Iran is scheduled to be signed today but Iran’s Islamic Revolutionary Guard Corps pushed back on the president’s timing, adding that “the memorandum has not yet been finalized.”

• Questions remain: The conflicting messages over the timing is the latest in a divergence in accounts between both sides. Qatari negotiators have traveled to Tehran to help facilitate the finalization of the agreement, a source told CNN.

• Next steps: Officials are planning for a virtual signing, sources told CNN. If the memorandum of understanding is signed, it would kick off a new 60-day period of negotiations, a US official said Friday.

When US President Donald Trump said an agreement with Iran is “scheduled to be signed” on Sunday, he added that “when all is calm, we will go in and get the Nuclear Dust, buried deep under the powerful sunken granite mountains.”