Investors may be getting a prime chance to play China.

That's at least according to KraneShares investment chief Brendan Ahern, who says that despite Monday's rally in U.S. equities, which took the to a new all-time high after the U.S. and China agreed to a trade truce, Chinese stocks are still looking fairly cheap.

"The truce that was struck over the weekend provides the opportunity for professional investors to come back into Chinese stocks," Ahern said Monday on CNBC's "ETF Edge." "The trade war ... overhang has depressed Chinese equities, and we believe that going forward, the truce provides a great entry point, a great opportunity for investors due to the depressed valuations on both a historical and relative basis."

In fact, on a price-to-book-value basis, Chinese stocks are the cheapest they've been relative to the S&P 500 in 20 years, said Ahern, whose firm operates 16 China-focused ETFs with $2.5 billion assets under management.

Price-to-book-value comparisons stack the underlying company's book value, or the value of all of its hard assets, against its trading price.

But that relatively poor performance is signaling that there could be improvement among Chinese stocks in the near term, Ahern said, adding that he could see them rallying back up to their March highs.

"The overhang of the trade war has kept the Chinese internet and e-commerce companies, the companies that are the transmission for domestic consumption in China, ... down," he said, pointing to KraneShares' CSI China Internet ETF, a popular fund that tracks shares of companies including Tencent and Alibaba.

"We really love KWEB today," he said as the ETF rallied over 2%. "Look at the non-manufacturing [purchasing managers' index] we got overnight. It's still in expansion territory. Retail sales in the month of May was up over 8%. The earnings of the companies we saw from our portfolio, very, very strong. The Chinese consumer is alive and well, we've just had the overhang of the trade war. If that dissipates, I think these names [and] KWEB can go on a run here."

Mary Ann Bartels, Bank of America-Merrill Lynch's head of ETF strategy, said that while she understands Ahern's optimism, her outlook for the U.S.-China trade debacle wasn't as bullish in the near term.

"We've kind of had some data come out of China, some green shoots, just like Brendan mentioned, that are actually positive," she said in the same "ETF Edge" interview. "When you do look at not only China, but emerging markets, they're really at extreme, depressed valuations."

But "we aren't expecting a trade negotiation anytime soon," Bartels said. "We think this is going to be long and drawn out. But for those investors that can take a very long time horizon and withstand volatility, taking a look at the emerging markets, which would include China, might be appropriate."

The iShares China Large-Cap ETF gained over 1% in Monday's trading session, even as U.S. markets lost steam towards the end of the day. KWEB, KraneShares' internet-based Chinese ETF, is now up 20% this year.

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