Der Spiegel magazine reported that Großmann met Alexey Miller, the head of Gazprom, in Paris on Friday to discuss potential investment opportunities that could see the Russian gas producer take a stake in RWE, Germany's second-largest power supplier.
Großmann hopes to be able to present the results of those negotiations to RWE's supervisory board by early August.
The RWE chief executive is seeking a new way forward in light of the German parliament's decision to abandon nuclear power by 2022 – which has Großmann mulling a strategic partnership between Gazprom and RWE or its subsidiaries.
That involvement could see Gazprom assume the role of major stakeholder in the German company. Gazprom's own majority stakeholder is the Russian government, which holds 51 percent of the company's shares.
Alexey Miller, Gazprom CEO, announced in recent weeks the company's intentions to expand on the German market, but RWE isn't the only company that has caught the Russian firm's attention.
Der Spiegel said Miller had also discussed potential partnerships with Johannes Teyssen, the head of German energy firm EON, on Thursday.
Germany gets more than 30 percent of its gas supply from Russia, and high prices have strained business ties between energy executives in the two countries. In 2008, natural gas supplied 13 percent of Germany's power consumption, according to figures from the German Association of Energy and Water Industries, BDEW.
The following year, natural gas met an estimated 19 percent of German homes' heating needs. With plans to scrap nuclear power in Germany in the works, gas stands to become an even more important power source in the years to come.