Protectionism will not improve competitiveness of the United States, and a trade war will hurt millions of small businesses and farmers in the country, Alibaba founder Jack Ma said in an opinion piece published in The Wall Street Journal on Wednesday.

In the article, Ma suggested that as China, the largest potential consumer market in the world, is open for business, the US risks forfeiting such an opportunity by waging a trade war.

His comments came at a time when the world's top two economies are embroidered in a bitter trade dispute.

Before the current spat, the Chinese e-commerce giant suffered a setback in the US in February, when the Committee on Foreign Investment in the United States blocked the $1.2 billion purchase of Dallas-based US money transfer company MoneyGram by Ant Financial, an affiliate of Alibaba.

The Donald Trump administration threatened to impose tariffs on $100 billion worth of Chinese products last week, in addition to a $50 billion tariff package proposed two days before, which provoked China into slapping 25 percent tariffs on imports of US soybeans, corn, airplanes and automobiles.

US soybeans sold to China account for 62 percent of its total soybean exports. A 25 percent tariff on the product will have a devastating effect on every soybean farmer in the US, American Soybean Association President John Heisdorffer said earlier last week.

"Instigating a trade war is the wrong solution because it will only provoke retaliation," Ma wrote. "The US has been a consistent defender of free and open markets, but this time it is resorting to protectionism that will not improve American competitiveness."

The billionaire made headlines at Trump Tower in New York early last January, when he and then president-elect Trump discussed "plans to create 1 million US jobs by allowing small- and medium-sized businesses to sell to China through Alibaba's platforms".

But the plan seems to be hitting a snag. At a discussion on Monday at the Boao Forum for Asia in Hainan province, South China, Ma said, "if China and the US have a good relationship, we cannot only make 1 million jobs, we can make 10 million or 20 million jobs for both countries," according to a livestream of the discussion.

"If they have no good trade relationship, we are going to destroy 10 million jobs," he added.

In Wednesday's article, however, Ma said his company is committed to supporting small businesses. Through its digital-commerce platforms, where at least 500 million Chinese consumers shop, Alibaba will continue to help US small businesses and farmers access the China market, he said.

Still, he cautioned, "this trade war will hurt millions of American small businesses and farmers".

Ma, however, remained upbeat about the future, saying that while facing setbacks in the current protectionist environment, "I remain confident and look forward to the next 20 years."