Tehran, Jun 28 (IANS): Abbas Araqchi, Iran's chief nuclear negotiator, has said that it is time for the parties involved in the negotiations aimed at reviving the 2015 nuclear deal to take "tough" decisions after "enough" discussions.

"There are a number of pending issues that have been sufficiently negotiated, and it is time for countries to decide," the senior diplomat told the official Islamic Consultative Assembly News Agency on Sunday, after a meeting with MPs earlier in the day.

Tehran, he added, has already taken its "tough decision" when it decided to stay in the nuclear agreement after the US under former President Donald Trump unilaterally quit it in May 2018, and then reimposed sanctions on Iran, reports Xinhua news agency.

It was Iran's "big and difficult" decision that has allowed so far to preserve the deal, formally known as Joint Comprehensive Plan of Action (JCPOA), Araqchi said.

Now it is time for Iran's counterparts to take their "tough decisions" after six rounds of meetings of the JCPOA Joint Commission, he added.

On Saturday, the spokesman for Iran's Foreign Ministry Saeed Khatibzadeh said the country will not negotiate endlessly, and urged the US to abandon the "failed legacy" of Trump.

The US government under Trump withdrew from the international deal in May 2018 and unilaterally reimposed sanctions on Iran.

In response, Iran gradually stopped implementing parts of its commitments to the agreement from May 2019.

Since April 6, the Joint Commission of the nuclear agreement have continued discussions about a possible return of the US to the deal and how to ensure the full and its effective implementation.