Mr Ahmadinejad, who was preparing to receive a top Russian security official, said he was looking to build a closer relationship with Moscow and expecting to see the Russian-built Bushehr nuclear power plant – Iran's first – start producing electricity next year, after many delays.
He brushed aside suggestions that his previous meetings with Dmitry Medvedev, Russian President, were clouded by disagreements and said the two neighbours could offer "joint solutions" to global problems.
"Nuclear weapons are the means of the previous century," Mr Ahmadinejad said.
"If any country tries to build a nuclear bomb, they waste their money and their resources."
His comments came as Russia's Security Concil Secretary Nikolai Patrushev prepared to open two-day talks in Tehran on Monday during which he is also expected to meet his Iranian counterpart and Foreign Minister Ali Akbar Salehi.
A Russian diplomat speaking to the Interfax news agency provided no details about what nuclear initiative Mr Patrushev might be taking into the Mr Ahmadinejad meeting.
But Moscow has previously balanced pressure on Tehran to engage in more open negotiations with condemnation of Western sanctions and some calls for a tougher international approach.