Federal Reserve Chairman Jerome Powell told the House Financial Services Committee on Wednesday that international trade tensions and a shaky global economy are putting a shadow on the U.S. economic forecast. 

"Inflation has been running below the Federal Open Market Committee's (FOMC) symmetric 2% objective, and crosscurrents, such as trade tensions and concerns about global growth, have been weighing on economic activity and the outlook," Powell said. He also added the central bank would "act as appropriate" to sustain U.S. economic expansion.

Stocks rallied Wednesday after Powell's comments amid hints that the central bank may cut interest rates this month.

“Powell’s prepared testimony struck a decidedly dovish cord with ‘uncertainties’ over trade and global growth since the June FOMC meeting characterized as having dimmed the outlook. By way of an update, the Chair just confirmed that things have gotten worse,” Ian Lyngen, head of U.S. rates at BMO Capital Markets, told CNBC.

Under President Donald Trump, the U.S. has levied tariffs on countries such as India and China, which has disrupted the interconnected global economy, as those countries then strike back at the tariffs. The World Bank has also suggested that global growth will slow down to 2.6% in 2019, a figure that is weaker than expected. 

Trump has been frequently critical of the Fed under Powell for not lowering rates to stimulate the economy. Powell's non-willingness to lower rates has given rise to rumors that Trump has planned to demote or fire Powell.

When asked by Rep. Maxine Waters, D-Calif., if he would resign if asked by Trump, Powell said "of course I would not do that." 

"The law clearly gives me a four-year term and I fully intend to serve it," Powell elaborated.

Also during the question and answer session, Powell criticized Facebook's proposed cryptocurrency, Libra, saying that it raises "serious concerns regarding privacy, money laundering, consumer protection, and financial stability."

"These are concerns that should be thoroughly and publicly addressed," Powell said.