“Vienna negotiations have reached a stage, where the outcome can be declared certainly and without the need for guesswork,” Secretary of Iran’s Supreme National Security Council (SNSC) Ali Shamkhani wrote in a tweet on Monday.

“The US political decision either to satisfy or dismiss requirements for the conclusion of a reliable and durable agreement based on JCPOA agreed-upon principles can replace speculation,” Shamkhani added.

Earlier, Iran's security chief Shamkhani warned the United States against putting up a "show" of lifting the sanctions rather than actually removing the bans. 

The eighth round of talks on the removal of all anti-Iranian sanctions kicked off on Dec. 27 in the Austrian capital of Vienna and is one of lengthy rounds of talks. These days, participants are busy active drafting the text of the agreement and deciding on some controversial issues.

The Islamic Republic of Iran has always stated that it is seeking a stable and reliable agreement and the US sanctions need to be removed in a verifiable manner, as well as Washington should provide guarantees that it will not pull out again.