"We will continue cooperation with the world community in tackling the problem, and we want to influence Iran to make it halt uranium enrichment activities and return to the negotiation table, in line with UN resolution requirements," Aso told reporters.
The UN Security Council has twice imposed sanctions against Iran since December for its refusal to halt uranium enrichment, which the country resumed in January 2006 for what it claims to be a civilian nuclear power-generating program.
Japan will add another 13 organizations and 15 individuals to the UN list of those linked to nuclear activities in Iran whose assets have been frozen.
In February, Tokyo blocked the assets of 10 organizations and 12 individuals, banned Iranian imports that could be linked to missile and nuclear technology and exports of sensitive material to Iran, and barred Iranians who could be part of the nuclear program from traveling to Japan.
Tokyo will also suspend financial aid to the country, except under humanitarian programs, and step up control over money transfers to Iran, Aso said.
The decision came after a bill to withdraw U.S. investment from foreign companies working in Iran's oil and gas sector and to protect the investment pullout from prosecution by foreign firms was introduced by Democrats to the Senate and Congress's House of Representatives of the United States, Japan's close ally, Wednesday.
The UN resolution set a 60-day deadline for Iran to comply. It expires May 23, following which the UN Security Council will consider further steps with regard to the defiant regime.
Iran first announced industrial production of civilian-grade nuclear fuel April 9 and vowed to continue uranium enrichment despite international sanctions.
UN inspectors visited Iran's Natanza nuclear center this week and confirmed that Tehran had attained an industrial-scale of uranium production. Some experts have said it could take the country about a year to build a nuclear bomb.
