A Chinese and U.S. flag at a booth during the first China International Import Expo in Shanghai, taken on taken on November 6, 2018.Johannes Eisele | AFP | Getty ImagesInvestors look set to make money when Washington and Beijing sign their “phase one” trade deal — but in the long term, the Sino-U.S. trade war is “unresolvable,” according to one analyst.Speaking to CNBC’s “Squawk Box Europe” on Tuesday, Patrick Armstrong, CIO of Plurimi Investment Managers, said holding any asset ahead of the agreement being finalized would definitely pay off.”The way to make money is easy right now, you just have to own something, because everything’s just been grinding higher,” he said. “No one wants to be short going into the day before the trade deal’s announced.”Markets have experienced volatility on the back of news relating to the U.S. and China’s “phase one” deal since President Donald Trump announced it was being negotiated in October. The U.S. president added fresh uncertainty to proceedings on Tuesday when he told reporters in London it might be better to wait until after the United States’ 2020 election to strike a deal with Beijing.Despite months of anticipation from markets, however, Armstrong speculated the preliminary deal would be a “sell the news type event” with little economic impact.”I think any trade deal we get between the U.S. and China is going to be very shallow,” he explained. “It’s not the all-encompassing deal we were hoping for.”He noted that investors had been expecting the “two biggest macro uncertainties” — Brexit and U.S.-China trade relations — to be resolved in early 2019, and markets were now entering 2020 still awaiting solutions.But according to Armstrong, there is no end in sight for the Sino-U.S. trade war.”I think U.S.-China is unresolvable,” he told CNBC. “I think what Trump did yesterday is a real warning that once he gets a deal with China — he’s combative, he wants to have an opponent — he’s going to change his attention from China to South America to Europe, and I don’t think we’re going to have a trade deal that just leads to a resumption of global trade.”Trump on Monday announced he would slap tariffs on steel and aluminum imported to the U.S. from Argentina and Brazil, accusing both nations of hurting American farmers by devaluing their currencies.Analysts have been weighing in on the potential economic impact of the U.S. and China’s “phase one” deal being signed for months. Many have speculated that while markets may respond positively to the prospect of a deal, its effect on the wider economy is likely to be limited.Speaking to CNBC’s “Street Signs” last week, Keyu Jin, associate professor of economics at London School of Economics, described the phase one agreement as a “face deal” that would be a political gift to Trump because it would encourage stocks to rally.Meanwhile, Yale University professor and former Morgan Stanley Asia Chairman Stephen Roach told CNBC in November that the deal was “pretty hollow” but “politically expedient, especially for the U.S. president.”Others have shared Armstrong’s pessimism on the longer-term outlook for the trade war.Andrew Sheets, chief cross-asset strategist at Morgan Stanley, told CNBC last month that the phase one agreement “might be about as good as it gets,” while Beat Wittmann, partner at Porta Advisors, said markets should not expect a comprehensive trade deal between the U.S. and China.