TEHRAN - The European Union's foreign policy chief said on Monday he hoped the United States would respond positively as early as this week to an EU proposal that aims to save a 2015 nuclear deal with Iran, US News reported.

Josep Borrell also said that Iran had given a "reasonable" response to the proposal, which follows 16 months of fitful, indirect U.S.-Iranian talks with the EU shuttling between the parties. The contents of the proposal have not been made public.

"There was a proposal from me as coordinator of the negotiations saying 'this is the equilibrium we reached, I don't think we can improve it on one side or the other'... and there was a response from Iran that I considered reasonable," Borrell told a university event in the Spanish city of Santander.

"It was transmitted to the United States which has not yet responded formally... I hope the response will put an end to the negotiations," he added.

An EU official has previously said the proposal is the bloc's "final offer" to revive a pact suspended in 2018 by the administration of then-U.S. President Donald Trump.

"The world would be a much safer place if we can make this agreement work," Borrell said.