Rosatom agreed to sell a stake in one of its uranium enrichment plants to the Kazakh state company Kazatomprom in a deal that would for the first time unlock a Russian nuclear fuel maker for partial foreign ownership, both companies said Tuesday.

Kazatomprom, the world's largest uranium producer, is hoping to complete the deal before the end of September, its chief, Vladimir Shkolnik, told reporters at an industry conference.

Rosatom, the state corporation that runs the country's nuclear industry, made the offer in the first quarter of this year, said Vladislav Korogodin, deputy chief of Rosatom's department for nuclear energy industry.

For sale is up to 49 percent in either the Uralsky Electrochemical Combine or the Electrochemical Plant, he said, Interfax reported.

The agreement replaces a previous accord that Russia, owner of 40 percent of global enrichment capacity, and Kazakhstan signed to jointly build an enrichment plant in Angarsk, Interfax said. The countries decided to use an existing facility for their cooperation because they determined that there was an excess of such facilities worldwide, the report said.

Shkolnik said the new deal would also “hopefully” allow Kazatomprom to market the venture's fuel-grade uranium independently of Rosatom. The companies could divide the markets to avoid competition, he said.

In another joint venture, the two companies are continuing to work on a plan to build a medium-capacity nuclear power plant in Kazakhstan, Shkolnik said. The project, now being studied by the Kazakh government, would provide a model for duplicating in any future contracts with third countries, he said.

Rosatom chief Sergei Kiriyenko said at the conference that Russia's trademark power reactors of at least 1.2 gigawatts capacity were too large for countries that are only starting to develop their nuclear power industries. Rosatom needs to rapidly develop small capacity models of up to 100 megawatts and medium-capacity models of 300 megawatts to 600 megawatts, he said.

As part of that policy, Rosatom is planning to take delivery of a barge later this month that will carry Russia's first floating nuclear power plant, Kiriyenko said. The 80-megawatt plant is scheduled to begin operating in 2012, he said.

Shkolnik estimated that medium-capacity plants account for 20 percent of demand for new nuclear power generation.

Also at the conference, Kiriyenko announced that Russia and Iran would jointly run Iran's first nuclear power plant that Rosatom plans to launch in August. Iran agreed to establish a joint venture with Rosatom to operate the plant because the country doesn't have enough experience in maintaining such facilities, he said.

In other news, Rosatom signed an agreement with the French Atomic Energy Commission to expand cooperation on reprocessing, decommissioning and isotopes technology.

In what could further extend Rosatom's international reach, the State Duma is scheduled to ratify an accord between Russia and Australia on peaceful nuclear cooperation on Wednesday. Australia holds the world's largest reserves of uranium and is the world's third-largest producer of the radioactive ore used to make nuclear fuel.

Under a deal signed in 2007, which Australia also has yet to ratify, Russia will be able to import Australian uranium for use at its own nuclear power plants after enrichment. That would allow Russia to create a “safety margin” of uranium reserves for its growing nuclear power generation, the Duma said on its web site Tuesday.

Australian Foreign Minister Stephen Smith said at the end of April that the country would ratify the agreement. He didn't say when.