​​​​​​​LONDON 

The Italian president warned against weakening UN treaties on Tuesday after “unacceptable allusions" emerged about the possibility of using nuclear weapons, according to the Italian news agency.

"It is necessary to strengthen -- not demolish -- the architecture relating to disarmament and the non-proliferation of nuclear weapons, at a time in history when, instead, we are witnessing unacceptable allusions to the use of weapons of mass destruction," Sergio Mattarella was quoted by ANSA.

His remarks came at an event in Vienna marking the 25th anniversary of the United Nations Convention against Transnational Organized Crime (UNTOC).

Saying that the UN can fulfil its mandate as a guarantor of international peace only if member states allow it to do so, Mattarella said the "UN remains, even with limitations, an extraordinary, irreplaceable instrument of peace and stability, which it would be irresponsible to weaken."

He went on to say that the UN continues to be the key framework for addressing challenges that transcend national boundaries, including challenges posed by artificial intelligence and the protection of global health.

It came after Russia said it successfully tested two nuclear-powered and nuclear-capable weapons last week.

Following that announcement, US President Donald Trump instructed the State Department to restart US nuclear testing "on an equal basis" to other countries.