PARIS - Diplomatic efforts to end the war in Iran are gathering pace, even though Tehran continues to insist talks with the United States are not happening.
Here is what we know about the behind-the-scenes mediation efforts:
What is on the table?
After announcing "very good" talks with an unnamed "top person" in Iran on Monday, Trump said Tuesday that he had sent a plan and that it "all starts with, they cannot have a nuclear weapon."
A 15-point proposal to stop the fighting has been conveyed to Iran via Pakistan, Pakistani officials have confirmed.
But the exact contents remain unknown and the identity of Trump's "top person" is a mystery, if he exists at all.
The New York Times and Al Jazeera have reported that Trump is proposing a one-month ceasefire during which the two sides would restart talks about the same issues they were discussing before the war.
These include a US demand that Iran hand over its enriched uranium stockpile, stop any further enrichment, and agree to limits on its missile programme, as well as cease support for militant groups in the region.
If Iran met US conditions and opened up the strategic Strait of Hormuz for shipping, which it has effectively closed, Trump is offering relief from all sanctions, the reports suggest.
After saying that Iran wanted to make a deal "so badly", the US president warned Thursday that they "better get serious soon".
The head of the UN nuclear watchdog Rafael Grossi has said a meeting in Islamabad at the weekend is under discussion.
What does Iran say?
Publicly, no Iranian official has confirmed any negotiations, but the language used is ambiguous.
Iranian Foreign Minister Abbas Araghchi said messages were "being exchanged through friendly countries or through certain different individuals" but insisted that "this is neither called dialogue nor negotiation".
But he added that "if it is necessary for a position to be taken, it will certainly be decided".
Pakistani and Egyptian officials have confirmed they are serving as diplomatic backchannels.
What are Iran's demands?
According to an unidentified Iranian official cited by Iran's Press TV on Wednesday, Tehran has sent five conditions for an end to hostilities.
These include ending "aggression and assassinations", setting up a mechanism guaranteeing that neither Israel nor the United States would resume the war, as well as financial compensation.
They also include a cessation of hostilities on all fronts, meaning Israel would stop bombarding Tehran-backed Hezbollah in Lebanon and possibly Hamas in Gaza.
The official also said Tehran wanted international recognition of its sovereignty over the Strait of Hormuz.
On March 11, Iranian President Masoud Pezeshkian laid out Iranian terms as "recognising Iran's legitimate rights, payment of reparations, and firm international guarantees against future aggression".
The Wall Street Journal reported that Tehran was also demanding the closure of US military bases in the Gulf.
Infographic with a map showing the key bridges over the Litani River in southern Lebanon (AFP)