Addressing the United Nations General Assembly underway in New York City, Lula reiterated sentiments that "work needs to be done to create space for negotiations."
"A lot is invested in weapons and very little in development," he said.
Lula, 77, who has faced accusations in the West of being soft on Russia over its invasion of Ukraine, will meet with his Ukrainian counterpart Volodymyr Zelensky on the sidelines of the General Assembly.
Zelensky had previously sought a one-on-one meeting with Lula at the G7 summit in Japan in May, but the attempt fizzled.
Relations are tense between Zelensky and Lula, who has said that the Ukrainian leader is "as responsible" for the war as Russian President Vladimir Putin and has refused to join Western nations in imposing sanctions on Russia or supplying munitions to Ukraine.
Lula has sought to position Brazil as a potential mediator in the conflict, along with other "neutral" countries, including China, India and Indonesia.
U.N. Secretary-General Antonio Guterres opened Tuesday’s addresses. Also scheduled to speak Tuesday are South African President Cyril Ramaphosa, Turkish President Recep Tayyip Erdoğan, and Iranian President Ebrahim Raisi.