Chinese stocks continued their upward trend on Wednesday as investors showed cautious optimism following the extension of a truce between the U.S. and Iran.

The Shanghai Composite Index, the main gauge of Chinese stocks, gained 0.5% or by 21.18 points to 4,106.26. The Shenzhen Component Index rose 1.3% or by 195.15 points to 15,177.29.

The rise comes as U.S. President Donald Trump said he would indefinitely extend a truce with Iran to accommodate more peace negotiations, Reuters reported separately Wednesday.

Investors seemed to have heaved a sigh of relief even if it was not yet clear whether Iran or Israel would adhere to the extension, Reuters said.

The market has also become increasingly numb to the effects of geopolitical tensions, with Middle East geopolitical risks gradually easing, according to the newswire, citing Nanhua Futures analysts.

In corporate news, China United Network Communications' (SHA:600050) shares dropped 3% during the closing bell following an 18% fall in first-quarter profit to 2.14 billion yuan.

China Petroleum & Chemical (SHA:600028) or Sinopec's Shanghai shares slipped 1% after one of its units trimmed its stake in battery giant Contemporary Amperex Technology (SHE:300750, HKG:3750) by 8.5 million shares, equivalent to HK$6 billion, multiple media reports said. CATL's Shenzhen shares fell nearly 1%.