UPDATE 1-Argentina, Germany want to keep pledge for free trade at G20 summit

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BUENOS AIRES, March 18 (Reuters) - Germany and Argentina want to uphold a pledge to keep international trade free at a summit of the world's 20 largest economies in Buenos Aires this week, the countries' finance ministers said on Sunday.

A multi-decade-old international consensus over international trade has come under threat from U.S. President Donald Trump's protectionist stance, which includes plans to impose tariffs on steel and aluminium.

But representatives from Europe's largest economy, Germany, and host country Argentina will insist on maintaining in the communique of a G20 summit on March 19-20 the language of the group's previous gathering, which stressed "the crucial role of the rules-based international trading system."

"We aim to reach an agreement in terms of maintaining the wording of the Hamburg communique (about) sustaining the benefits of free trade," Argentina's Treasury Minister Nicolas Dujovne, the host of the G20 summit, said.

His words were echoed by Germany's new Social Democratic finance minister Olaf Scholz, who was speaking alongside him at a press conference after a bilateral meeting.

Their comments confirm a draft of the communique exclusively seen by Reuters last week.

Speaking to reporters earlier, Scholz had also warned that protectionism could harm future economic prospects and said Germany would continue talks to dissuade the United States from imposing planned punitive tariffs.

He also pledged to invest more in Germany's public infrastructure - something Germany's European partners have long called for in hopes it would help stimulate the region's economy as a whole.

"Germany is a very strong economy and the new government will invest a lot to... increase the investment in the public infrastructure, which is part of the debate we have all over the world," Scholz said.

This marked a departure from his predecessor, austerity champion Wolfgang Schaeuble. (Reporting by Franceso Canepa; Additional Reporting By Gernot Heller; Editing by Andrea Ricci)