According to a media report, US Secretary of State Marco Rubio has agreed with his counterparts from Germany, France and Great Britain to set the end of August as the deadline for reaching a nuclear agreement with Iran.

The foreign ministers of the four countries agreed to this in a telephone call on Monday, the US news site "Axios" reported, citing three people familiar with the conversation.

US State Department spokeswoman Tammy Bruce said on Monday that the conversation focused on preventing Iran from having a nuclear weapon. However, she did not provide further details.

What is planned if the deadline is not met

According to Axios, the three European countries plan to use the so-called snapback mechanism to trigger sanctions against Tehran if no agreement is reached by the deadline. The 2015 Vienna agreement on Iran's nuclear program formally expires this October. As co-signatories, the Europeans have the option of using the snapback mechanism to reinstate previous, strict UN sanctions against Iran without much resistance.

German Foreign Minister Johann Wadephul (CDU) had already stated a few weeks ago that the Europeans could resort to this. "We have a real trump card. Washington knows that, and we will use it together in a coordinated manner," he said on ZDF at the end of last month. He also reiterated the goal of a negotiated solution.

According to information from Axios, the Europeans plan to approach Iran in the coming days and weeks with the message that the country can avoid triggering sanctions if it takes steps to reassure the world about its nuclear program.