US President Donald Trump said he wanted the US to become a technology leader through competition rather than blocking others.
Trump said US companies need to "strengthen their efforts or stay behind".
He did not specifically mention China's Huawei, although many interpreted the remarks as Trump takes a softer stance toward the company.
The US has pressured allies to exclude the Chinese telecom giant from its future 5G mobile networks.
Some governments have endorsed Huawei for security reasons to deliver parts of their networks, but British cyber security chiefs recently said the risks are manageable.
In a tweet, Trump said he wanted "5G and even 6G technology in the United States as soon as possible".
"I want the US to win through competition, not by blocking more advanced technologies."
"American companies need to increase their efforts or stay behind," he said.
It came when the founder of Huawei Ren Zhengfei said defiantly in an interview with the BBC this week that "there is no way for the US to destroy the company."
Some US allies have also taken a softer stance on Huawei lately.
British cyber security chiefs said last week that any risk arising from Huawei's involvement in UK telecommunications projects can be managed, while recent media reports suggest that Germany is unwilling to foreclose Huawei from its 5G network.
The dispute over Huawei is part of the tensions between the two largest economies in the world, whose officials are currently in Washington trying to end their trade war.
Mr. Trump will meet Chinese Vice Prime Minister Liu He on Friday as both sides try to reach a deal before March 1st.
Both countries have introduced tariffs on billions of dollars worth of goods since last July.