UPDATE 1-Germany alarmed by resignation of top Trump economic adviser

(Adds Zypries quotes, background)

BERLIN, March 7 (Reuters) - The German government has grave concerns about the resignation of U.S. President Donald Trump's top economic adviser, Economy Minister Brigitte Zypries said on Wednesday, adding that she hoped Trump would change his mind on import tariffs.

"The situation is serious," Zypries said about Trump's decision to impose hefty tariffs on metals and the departure of Gary Cohn, who was seen as a moderating voice in the White House.

Zypries said Berlin was closely coordinating its next steps with other European Union member states, adding that Europe would respond in an appropriate manner if the U.S. imposed tariffs on steel and aluminum.

But she also said Germany hoped to avoid a trade conflict. "I hope Trump changes his mind," Zypries said.

The minister said she was convinced that trade ensured prosperity for all if it was based on mutual understanding.

"It's very important that there are advocates for this in the White House," Zypries said. "That's why I'm worried about the latest signals coming from the USA."

Trump's adviser Cohn, a former Goldman Sachs chief executive, said on Tuesday he would resign. He had lost a fight over Trump's plans for hefty import tariffs and his departure is seen as raising the chances of a global trade war.

The news has rattled European and U.S. markets.

Trump said in a tweet on Tuesday night that he would decide soon who would replace Cohn. White House officials said the tariffs dispute contributed to Cohn's decision to leave but that it was not the sole reason.

Trump also warned the European Union it would get hit with a "big tax of 25 percent on their cars" for not treating the United States well when it comes to trade.

Trump's trade threats have alarmed German carmakers who urged policymakers on Monday to avoid a trade war with the United States "at all costs".

The United States is the second-biggest export destination for German auto manufacturers after China, while vehicles and car parts are Germany's biggest source of export income.

Analysts fear a full-blown trade war between the United States and Europe could cut growth in Germany, the biggest European economy, by up to 1 percentage point. (Reporting by Gernot Heller and Michael Nienaber Editing by Catherine Evans)