200 Iranian MPs have issued a letter urging the country’s nuclear negotiating team to reject restrictions or a ban on the use of the heavy water reactor in Arak.

They also insist that Iran’s defence matters and ballistic capacities should not be compromised in the negotiations.

A new round of nuclear talks between Iran and the 5+1 will begin this week in Vienna.

The letter indicates that Iran is committed to the NPT agreement and any agreement with the 5+1 should not create “restrictions or a ban on activities regarding research, especially the development of the heavy water reactor and enrichment.”

The letter states that such an agreement will not be accepted by the parliamentary representatives of the people of Iran.

U.S. officials have indicated that Iran’s ballistic capability will be one of the topics of discussion in Vienna.