President Donald Trump's speech targeting China's intellectual property and trade practices has been postponed, sources told CNBC.

People close to the event said it has been postponed with no explanation given and no reschedule date provided.

On Wednesday, senior White House officials confirmed to CNBC that the president was set to criticize Beijing's practices and sign a memo asking U.S. Trade Representative Robert Lighthizer to look into the matter.

Reuters previously reported, citing sources, that Lighthizer would initiate an investigation under the Trade Act of 1974's Section 301, which allows the president to unilaterally impose tariffs or other trade restrictions to protect U.S. industries.

China's initial response to these reports has been critical, but subdued.

Before news of the postponement, a spokesman for the Chinese Commerce Ministry pushed back against allegations that China has not done enough to protect intellectual property.

When asked about potential investigations and restrictions out of Washington, ministry spokesman Gao Feng reiterated Beijing's position that disputes should be taken to the World Trade Organization.

Government officials told CNBC that China is waiting to see if Trump will actually take action and what the details of any measures might be.

As a candidate, Trump appealed to voters in struggling manufacturing regions largely by saying he would impose restrictions on imports from China, especially in the form of tariffs.

— Reporting by CNBC's Kayla Tausche, Lori Ann LaRocco and Eunice Yoon.