A trade deal between China and the United States will be struck before the end of the year, forecasts David Rubenstein, co-founder and co-executive chairman of U.S. private equity company Carlyle Group.

Rubenstein said he is convinced that there will be an agreement announced in very near future.

"I think they've largely agreed to the terms. There are a few things that probably have to be resolved, but I do think there's an agreement that is going to be announced relatively soon. I think it'll be announced before the end of the year," he told CGTN.

Rubenstein identified the U.S. and China as the world's top two countries to invest in.

He endorsed the rule of law, transparency and quality markets in the U.S., saying that in his view it was the best place to invest.

But China is also an important destination for Carlyle to invest in. Rubenstein said that Carlyle had been a large investor in China and would continue to be so.

"The second best place (to invest) I would say is China, because of the size of the population, the welcoming of private equity investors from outside (and) a kind of capitalist spirit that exists here," he said.

Healthcare sector will play its part in Chinese market

Rubenstein is particularly bullish on China's healthcare sector.

He noted that as China switches to becoming a more consumer-oriented economy rather than export-led, companies that cater to the services industry will be very important.

"When I worked in the White House in the 1970s, roughly seven percent of the GDP (gross domestic product) of the United States was healthcare. Now it's about twenty percent. It's not quite as big a percentage of the economy in China, but it will be."

As emerging markets develop, "the middle class says, 'I like life. I want to live longer.' And so they get more and more healthcare-oriented services and products. That will happen in China, is happening in China."

Diversification is key to invest

Rubenstein also emphasized the importance of diversification when investing.

The most important thing is to not lose what you have, he said. The best way to do this is to "take relatively conservative positions and diversify. So don't put all your eggs in one basket," he explained.

He continued, "Don't think you're a genius because you made money in area A, and that you're going to make money investing in area B or C. So diversify what you have, try many different things don't be tied up in any one stock, any one industry, any one area, any one country."

Based on his point of view, investors should diversify their portfolios and seek a reasonable — rather than a heroic — rate of return.