At the same time, China is facing growing capital outflow pressure as the US Federal Reserve is raising interest rates.
It comes as the U.S. and China have imposed tariffs on one another's goods in a row that is hitting companies and risks hurting the global economy.
It is the fourth such move this year, as China seeks to blunt the economic impact US President Donald Trump's imposition of $250 billion dollars of Chinese goods, roughly half of country's exports to the US.
Mr. Pence's speech marked a sharpened US approach toward China, going beyond the bitter trade war between the world's two biggest economies, which has magnified concerns about the outlook for China's economy. Chinese dealers were playing catch-up with sharp losses last week, when Bloomberg reported that Beijing inserted microchips into equipment made in China for Amazon and Apple, and possibly for other companies and government agencies.
Chilling global markets on Monday, Chinese shares .CSI300.SSEC slumped and the yuan CNY=CFXS fell despite Beijing saying it would slash the amount of cash that commercial lenders need to set aside, releasing a net 750 billion yuan ($108 billion) into the banking system.
However, the decline also threatens to damage the Chinese economy by encouraging capital to flow out of the world's second-largest economy, increasing borrowing costs at a time when communist leaders are trying to shore up cooling growth.
"China's foreign-exchange reserves should decline given a stronger dollar and increasing depreciation pressures on the yuan, which could prompt the PBOC to intervene", said Ken Cheung, a senior currency strategist at Mizuho Bank Ltd. "There is room for further reductions and I expect another 1 percentage point cut by the year-end".More news: South African finance minister Nene resigns over Gupta scandal
The PBOC would "maintain reasonably ample liquidity to drive the reasonable growth of monetary credit and social financing scale", it said.
Tourism spending by domestic travellers in the first four days of the National Day holiday, which ended on Sunday, rose just 8.1% from previous year, which is much less than the 21% growth recorded in 2017, according to figures from the China Tourism Academy.
Shares in Asia slumped Monday as China's markets stumbled in their first trading day after a one-week holiday even though Beijing's central bank increased liquidity to offset the impact of an escalating trade dispute with the United States.
Coming on the final day of the National Day holiday, the South China Morning Post says "the central bank's announcement may also serve as a shot in the arm for the China's stock market when trading resumes on Monday morning". July saw a rise in nationwide jobless rate to 5.1%.
China's banking regulator has asked banks to significantly lower funding costs for smaller firms and raise their tolerance for non-performing ratios for loans to small and micro firms.
It is likely that further RRR cuts in addition to fiscal stimulus are in the pipeline to cushion the slowdown in the economy.