Cai Wei, Chinese consul general in Houston, released an open letter on Friday afternoon, shortly before the deadline given by the US government to close his consulate.

In the open letter, Cai said the US action "seriously violated international law and the norm of international relations, seriously violated the relevant provisions of the Sino-US consular treaty, and deliberately undermined Sino-US relations. China strongly condemns and firmly opposes this."

Less than one hour after 4 pm, US federal agents and local law enforcement entered the Chinese consulate compound while a crowd watched on the edge of the building. It is believed that Chinese consulate staff had left the building by then.

As the first Chinese consulate opened in the United States after the establishment of diplomatic relations between China and the US, "generations of diplomatic and consular staff have actively devoted themselves to the noble cause of enhancing Sino-US friendship," Cai said.

Much has been achieved. Cai pointed out that in 2018, total trade volume between China and the consular area reached $125.1 billion and total investment of Chinese companies in the consular area currently exceeds $20 billion.

The consulate general has weathered disasters with the people of Houston, Texas and eight Southern states in its consular district, Cai said. Be it Hurricane Harvey or the novel coronavirus epidemic that's still raging in the US, the consulate general has cooperated with American people to face the challenges together.

Cai recalled some of his interactions since he assumed the post in August last year.

"I have visited all eight states in the consular district. I remember that at the Flying Tigers Memorial in Baton Rouge, Louisiana, the descendants of the Flying Tigers and I gathered together, and I deeply felt the profound friendship formed by the Chinese and American people when they resisted aggression together," Cai said.

"I remember, at Herman Park in Houston, a little boy took the initiative to talk to me in Chinese and told me that he likes China and hopes to travel to China one day. These bits of memories warm my heart and I will remember them forever," Cai said in the statement.

Cai emphasized that the essence of Sino-US relations is mutual benefit and win-win results. Both sides should commit themselves to non-conflict, non-confrontation, mutual respect, and win-win cooperation, and jointly advance China-US relations based on coordination, cooperation, and stability.

He promised that the bilateral exchanges between the Chinese government and the southern region of the United States will not stop, and services to overseas Chinese will not stop. The Chinese embassy in the United States will make proper arrangement for friendly cooperation and consular services between China and the Southern US.

The closing of the consulate general of China in Houston will hurt travel, trade and the longstanding relationship between Houston and China, said Bob Harvey, CEO of the Greater Houston Partnership, according to report by the Houston Chronicle.

"Houston has had a special relationship with China going back to George Herbert Walker Bush," Harvey was quoted saying. "We've been able to maintain that warm relationship, even when we've had meaningful disputes. The lack of a Chinese consulate will hurt and will be a setback for Houston."

Charles Foster, chairman of US China Partnership, said Trump's move to close the consulate is political.

"The president is looking for someone to blame on his failures in handling the coronavirus and to blame on the economy," he said.

US Veteran diplomat Charles Freeman Jr, who was the main interpreter for President Richard Nixon during his 1972 China visit, shares a similar view, saying China is "being used as the whole purpose scapegoat".

"The China hawks in the administration have managed through a relentless campaign of propaganda to demonize China across the whole country," he said.

Freeman speculates that the consulate's closure was partially because Trump wants to stimulate his presidential opponent Biden to criticize his closing the Chinese consulate in Houston so he can call Biden "soft on China".

Dong Leshuo in Washington contributed to this story.