Iran is signaling an apparent readiness for more concessions over its nuclear program, this time on over its heavy-water reactor at Arak.

The semi-official Mehr news agency Friday quoted nuclear chief Ali Akbar Salehi as saying Tehran can modify the reactor's design so it would "produce less plutonium, to reduce concerns" by the West.

Salehi did not elaborate but his remarks came ahead of negotiations with world powers later in February about a long-term deal on Iran's disputed nuclear program.

The West fears that if Arak goes online, it could produce plutonium, which could eventually be used for nuclear weapons. Iran denies it wants to make an atomic bomb.

Under a landmark November deal, Tehran stopped enrichment of uranium to 20 percent in exchange for easing of some Western sanctions