German Chancellor Friedrich Merz urged Ukrainian President Volodymyr Zelenskyy in a call Thursday to sort out the country’s corruption problems as Kyiv faces the fallout of a massive scandal involving kickbacks.

“The chancellor emphasized the German government’s expectation that Ukraine will vigorously advance the fight against corruption and continue reforms, particularly in the area of the rule of law,” the chancellor’s spokesman said.

The government in Kyiv has been rocked by a corruption scandal this week involving allegations of kickbacks at a state nuclear energy company adding up to roughly $100 million. Zelenskyy wasn’t directly implicated, but the scandal strikes close to his inner circle and has led to the resignation of two ministers.

German government officials worry news of corruption in Ukraine will undermine public support for the embattled country. Merz has sought to strongly back Ukraine at a time when many European officials see the Trump administration as waffling on U.S. military support.

Germany has provided more weapons aid to Ukraine than any other European country.

Zelenskyy “pledged complete transparency, long-term support for the independent anti-corruption authorities, and further swift measures to regain the trust of the Ukrainian people, European partners, and international donors,” Merz’s spokesman also said.

Zelenskyy thanked the chancellor for German military support “particularly in the areas of air defense and protection of Ukraine’s energy infrastructure,” according to the chancellor’s spokesman.

“Germany, together with its Western partners, will increase pressure on Moscow to persuade Russia to engage in serious negotiations,” he added, including by “continuing work on making more effective use of immobilized Russian state assets.”