Technically heavy Nasdaq's composite index rose by 2.2 percent after strong gains among others in electric car manufacturer Tesla and chip giant Nvidia, up 5.4 and 2.9 percent respectively.
Dow Jones industrial index increased by 1.3 percent.
The index gains came after President Donald Trump toned down his statement on Friday, when he threatened to raise tariffs on Chinese goods by 100 percent. Now he wrote on the platform Truth Social that the US "wants to help China, not harm the country!!!".
The violent swings on the stock market are reminiscent of those in April, when Trump shocked investors with his so-called "Liberation day". The President then threatened to introduce sky-high tariffs against almost all countries in the world - only to later back down and initiate negotiations on trade policy.
