Beijing has voiced its strong dissatisfaction and firm opposition to the Taiwan Travel Act in the United States and has lodged solemn representations with Washington over the bill.

The bill, aiming to encourage official visits between the United States and Taiwan and passed by the US House of Representatives in January, was approved by the US Senate on Wednesday, the US Congress website shows.

It has to be signed by US President Donald Trump to become law.

"Though relevant clauses of the bill are not legally binding, the bill has severely violated the one-China principle and the stipulations of the three joint communiques between China and the US," Foreign Ministry spokeswoman Hua Chunying said on Thursday.

The one-China principle is the political foundation of China-US ties, Hua said, urging the US to observe its promises to stick to the one-China policy and abide by the three joint communiques.

Hua also urged the US to stop official exchanges as well as its elevation of ties with Taiwan and deal with Taiwan-related issues carefully and appropriately in order to avoid disruption or damage to China-US ties.

The US established diplomatic ties with Beijing and severed such ties with Taiwan in 1979.

Ruan Zongze, vice-president of the China Institute of International Studies, said the move by the US Senate shows that the US is trying to "play the Taiwan card" to contain China and increase its leverage in ties with China.

Such "bad ideas" will only backfire, Ruan said, warning that "the US should not harbor any illusions".

"China has never compromised, and will not compromise when it comes to safeguarding the one-China policy," he said, adding that China will take countermeasures against the "destructive" US practice.

In another development, Hua dismissed on Thursday key US military officers' recent comments.

CNBC quoted John Hyten, commander of US Strategic Command, as saying on Wednesday that China poses unique threats to the US. Also, Joseph Votel, commander of the US Central Command, talked on Tuesday about "China's growing military ambitions" in the Middle East, the Washington Post reported.

In response, Hua said it is strange that the US, "the number one military power in the world" with a military expenditure "way ahead" of those of other countries, tends so often to call others a threat. She questioned the true intention behind such "China threat" voices.

China's strategic intention is very transparent, the spokeswoman said, urging the US to view the development of the world as well as China objectively.