Nissan Motor Co.’s hands-off labor union stepped in to criticize the French government over its power struggle with Chief Executive Officer Carlos Ghosn, issuing its first public appeal involving the Japanese carmaker’s affairs in 16 years, reports BloombergBusiness.

The French government’s “unacceptable” attempt to obtain double voting rights in Renault SA would destabilize the two carmakers’ alliance, Nissan’s union said in a statement Wednesday. The labor group last shared its views this way in response to Ghosn’s rescue plan calling for Nissan plant closures in 1999, said Hiroyuki Ohkita, president of the union.

“We hope this matter can be resolved as soon as possible so that we can reestablish the foundations of a successful alliance while preserving the independence of Nissan,” the union said.

The clash between Nissan and France’s government risks undermining one of the auto industry’s most successful partnerships. Nissan has been considering ways to restructure its alliance with Renault after the government increased its stake in the French carmaker in April. Nissan has laid out a scenario to Renault board members in October that would grant the Japanese company voting rights in its partner, reversing what’s been an alliance with one-sided control, people familiar with the situation have said.

Nissan rose 0.7 percent at the close Thursday in Tokyo trading. The shares have climbed 23 percent this year, outpacing the 14 percent gain for the benchmark Topix index.

The partnership has been held together by the unequal cross shareholdings and Ghosn, 61, the CEO of both companies. Renault owns 43 percent of Nissan, which in turn holds 15 percent of its partner. Under French law, Nissan doesn’t have voting rights for its stake.

Nissan has suggested more balanced holdings with Renault in a range of 25 percent to 35 percent to Renault’s board members, the people said. Voting rights could be revived if Renault’s stake falls to less than 40 percent, and the French carmaker is also considering that move, people familiar with the situation said.