By Agence France-Presse
Forty new import barriers were erected by G20 states between mid-May and mid-October this year -- six times more than during the preceding six months -- impacting $481 billion in trade, a fresh WTO report showed.
That was the highest figure recorded since the WTO started calculating the measure in 2012.
"The report's findings should be of serious concern for G20 governments and the whole international community," WTO chief Roberto Azevedo said in a statement.
"Further escalation remains a real threat," he warned, calling for an immediate reversal of the trend.
"If we continue along the current course, the economic risks will increase, with potential effects for growth, jobs and consumer prices around the world," Azevedo said.
An average of eight new restrictions on international trade, including tariff increases, import bans and export duties, were imposed by the big economies each month, the report showed.
The report appears to show the impact of US President Donald Trump's relentlessly confrontational trade policy, including launching a trade war with China and slapping stiff tariffs on steel and alumium imports from many countries.
On Wednesday, the WTO's Dispute Settlement Body agreed to review complaints from a range of countries over the US tariffs, as well as Washington's complaints over retaliatory duties.
"The WTO is doing all it can to support efforts to de-escalate the situation, but finding solutions will require political will and it will require leadership from the G20," Azevedo said.