Martin Schulz, chairman of Germany's Social Democratic Party | Adam Berry/Getty Images German leaders must stop dictating terms, says Martin Schulz The Social Democrat challenger to Angela Merkel says it is unfair to expect Emmanuel Macron to do so much at the same time.

PARIS — German leaders must stop dictating terms to other European countries and show more solidarity, said Martin Schulz, the main challenger to Angela Merkel in Germany's parliamentary election this fall.

"This attitude, which consists of dictating to others what they must do, has to stop," Martin Schulz, chairman of Germany's Social Democratic Party (SPD), told Le Monde in an interview published Monday.

"Germany is not a professor, France is not a student," he added. "I don't belong to the category of political leaders who tell other countries: show us what work you're carrying out at home.' If President [Emmanuel] Macron says 'I want to reform France' and I tell him at the same time 'make savings,' that does not work."

Macron is under fire at home over planned budget cuts affecting multiple sectors, notably the army.

The French president is trying to bring France's budget deficit under 3 percent of gross domestic product by the end of this year. German conservatives in Merkel's government support the initiative, which would put France's finances in line with a European Union target. At the same time, Macron's government is preparing to unveil labor reforms that are deeply controversial at home. Street protests are already planned for September.

Macron's bold plans have already hurt the president's popularity. Between May and June, his approval rating plummeted by 10 percentage points to 54 percent, according to an Ifop poll published Sunday.

Schulz said it was not fair to expect Macron to do so much at the same time. "When [former German Chancellor Gerhard] Schröder reformed Germany, he broke the deficit reduction rules," he added.

Polls show Schulz 's SPD trailing Merkel's conservative bloc by a wide margin ahead of the September 24 election. But even if the SPD does not win the vote, it could reprise its current role in government as Merkel's junior coalition partner.

Schulz, a former president of the European Parliament, traveled to Paris last week in an effort to play up his foreign policy credentials and present himself to Macron as an ideal political partner for carrying out future eurozone reforms.

The French president's official agenda, however, made no mention of a meeting with Schulz. When Macron was running for president, he met with Merkel in Germany.

Schulz, who told Le Monde he could still win in the fall, accused Merkel of standing in the way of European reform.

"If Merkel was ready to change something, why is it only happening after 12 years? For years, German conservatives said no. That's why I think a change of government in Germany can be a good thing for France," he said.