Trade deals and the reform of WTO are better than trade wars. Trade wars will lead to recession, while trade deals will boost economy, said Donald Tusk, president of the European Council, on Saturday. He called for putting a stop to trade wars.

"Trade wars among G7 members will lead to eroding the already weakened trust among us," he said during a press conference prior to the G7 summit.

US President Donald Trump tweeted Friday that the US will raise existing duties on 250 billion US dollars of Chinese products from 25 percent to 30 percent beginning on Oct. 1, and another 300 billion dollars worth of Chinese imports will see tariff rise from 10 percent to 15 percent on Sept. 1.

If Trump uses tariffs for political reasons it would be risky to the whole world, including the European Union, Tusk told reporters.

China is firmly opposed to the US announcement that it will further raise the tariffs on about 550 billion US dollars of Chinese imports, said a spokesperson of China's Ministry of Commerce Saturday.

"Such unilateral and bullying acts of trade protectionism and extreme pressure run counter to the consensus of the heads of state of China and the United States, and run counter to the principles of mutual respect, equality and mutual benefit," the spokesperson said.

"China strongly urges the United States not to misjudge the situation, or underestimate the determination of the Chinese people. It must immediately stop its erroneous practices, or bear all the consequences," the spokesperson said.

Besides China, the US is currently at loggerheads with many countries, including G7 alliance from trade to security. Threatening Germany with car tariffs, Trump vowed to tax French wines if Paris levies digital tax on big US technology companies; Casting Canada as a trade villain who "robs US blindly", he also sniffed at the European integration by encouraging Brexit with a "great trade deal" with London; Withdrawal from the Paris climate accord and the Intermediate-Range Nuclear Forces Treaty one after another, he even showed his willingness to pull out some American forces in Germany unless Berlin increases defense spending to the 2-percent GDP threshold.

French President Emmanuel Macron on Saturday treated his G7 colleagues in France's luxurious seaside resort Biarritz, a long-time summer playground of Europe's elites, to tackle rising global inequality.

The G7 summit, the club of wealth countries, is facing unity crisis, with its pride and influence going downhill. With his America First policy, President Trump has turned the G7 into a "G6 vs G1" game. The embarrassment was vividly told by a picture taken during the Quebec summit in Canada last year, showing Trump sitting with arms crossed in a defensive posture while German Chancellor Angela Merkel, centered by the other G7 leaders, leaned across the table at him.

Meanwhile, as every member has been mired in different sort of problems -- be it political, partisan, economic, societal or diplomatic -- the "top student club" is drastically losing its charm, legitimacy and even capability in providing global leadership.

"This is another G7 summit which will be a difficult test of unity and solidarity of the free world and its leaders. There is still no certainty whether the group will be able to find common solutions, and the global challenges are today really serious, or whether it will focus on senseless disputes among each other," Tusk told reporters at the conference.

"The last years have shown that it is increasingly difficult for all of us to find common language when the world needs our cooperation more, not less. This may be the last moment to restore our political community," he warned.

Meanwhile on Brexit, Tusk called on British Prime Minister Boris Johnson not to go down history as "Mr. No Deal".

"Tomorrow, on the margins of the summit, I will have a meeting with Prime Minister Boris Johnson. He will be the third, British Conservative, Prime Minister, with whom I will discuss Brexit. The EU was always open to cooperation... and we will also be ready now to hold serious talks with PM Johnson," he added.

"The one thing I will not cooperate on is no deal. And I still hope that PM Johnson will not like to go down in history as Mr No Deal. We are willing to listen to ideas that are operational, realistic, and acceptable to all Member States including Ireland, if and when the UK government is ready to put them on the table," he noted.

Before landing in Biarritz, British Prime Minister Johnson visited Berlin and Paris on Wednesday and Thursday. In Paris, President Macron told Johnson that there was not enough time to wholly rewrite Britain's Brexit divorce deal before an Oct. 31 deadline.

In Berlin, German Chancellor Angela Merkel said the backstop of Irish border was intended only as a transitional rule.

She also emphasized the interest in a "negotiated withdrawal", but at the same time said that "We are also prepared if such a negotiated withdrawal does not exist".

"But you might find them in the next 30 days. Why not? Then we're a long way ahead," said Merkel, adding that border controls between Northern Ireland and Ireland would become superfluous and that the integrity of the single market could be safeguarded if Britain and the EU re-define their future relations.