The statement is strongly supported by two substantively aligned sources. TIME’s 'What to Know About Iran’s Ceasefire Proposal as Peace Talks Approach' directly reports that White House Press Secretary Karoline Leavitt said Iran’s original 10-point proposal was unacceptable and discarded, and that a later revised plan was more reasonable and served as a workable basis for negotiations. Al Jazeera’s 'Has Iran’s 10-point plan changed, as JD Vance claims?' independently corroborates the same core points and explicitly states that Leavitt said the revised Iranian plan could be aligned with Trump’s 15-point proposal while reaffirming that Trump’s red line on ending Iranian uranium enrichment had not changed. CBS News provides contextual corroboration on the ceasefire and negotiation framework, though it is less direct than TIME and Al Jazeera in the fetched excerpt. The user’s date of April 8 is slightly less certain from the fetched pages, since the articles were published April 9 while describing Leavitt’s Wednesday briefing, but the substance of the quoted claim is well supported.