Expectations are growing that US lawmakers are close to agreeing an almost $2tn plan to ease the economic impact of the coronavirus pandemic.
In the US, the Dow Jones Industrial Average saw its biggest one-day gain in almost nine decades.
The moves continue a pattern of extreme volatility on financial markets as investors grapple with the effects of the outbreak.
In morning trade Japan's benchmark Nikkei 225 gained 5.4%, the Hang Seng in Hong Kong rose 3.3%, and China's Shanghai Composite was up by 1.9%.
It continues a period of unprecedented volatility as markets react wildly to the economic impact of the coronavirus pandemic.
This month alone has seen the Dow having the five biggest daily gains and five biggest falls of its 135-year history.
On Wall Street, the Dow Jones Industrial Average surged by 11.4% on Tuesday, as it saw its biggest one-day gain since 1933. (BBC)