Beijing will make a legitimate and necessary response if Washington does not revoke its wrong decision on the closure of China's consulate-general in Houston, Foreign Ministry spokesman Wang Wenbin said on Wednesday, calling the move a provocation unilaterally initiated by the United States against China.

"China strongly condemns this outrageous and unjustified move to sabotage China-US relations," Wang said.

The spokesman confirmed at a regular media briefing in Beijing that the US abruptly told China on Tuesday to close its consulate-general in Houston, which Wang said violated international law, basic norms governing international relations and relevant stipulations of a bilateral consular agreement.

After China became a party to the Vienna Convention on Consular Relations in 1979, China and the US reached an agreement on the mutual establishment of consular relations and the opening of consulates-general. The consulate-general in Houston is one of two which opened that year.

US State Department spokeswoman Morgan Ortagus said on Wednesday that the directive to close China's consulate-general in Houston had been made to protect American intellectual property and the private information of its citizens.

According to Wang, the unilateral closure of the consulate-general in Houston within a short time is an unprecedented escalation of Washington's recent actions against China, and the US campaign of shifting blame and discrediting China had been going on for quite some time.

The US side has been attacking China's political system, harassing Chinese diplomatic staff in the US for no reason, intimidating and interrogating Chinese students in the US, and sometimes even seizing their electronic equipment or detaining them for no good reason, he said.

Wang noted that the US side, last October and in June this year, placed unwarranted limitations on Chinese diplomatic staff and it opened diplomatic parcels and searched the property of Chinese staff several times.

He said that as a result of the campaign to discredit China, "the Chinese embassy in the US has received death threats and bomb threats", adding that the US embassy in China has published articles attacking China's political system.

On Wednesday, Chinese news website the Paper cited sources saying that the visa office of the Chinese embassy in the US received a call from an unknown number in which a man said, "Do you know what's in your lobby?"

The man imitated the sound of an explosion and then ended the call, according to the report.

The spokesman said that in comparison, China always upholds the principle of noninterference in other countries' internal affairs and its diplomatic missions in the US have been working to enhance mutual trust and friendship between the two peoples.

China has been providing convenience to US diplomatic staff in China according to the Vienna Convention on Diplomatic Relations and the Vienna Convention on Consular Relations, he said.

"It is not difficult to answer the question on who is interfering in other countries' internal affairs and who is stirring up confrontation," Wang said.

If the US is bent on going down this wrong path, China will resolutely respond, he added.

Besides the consulate-general in Houston, China has another four in the US: in New York, San Francisco, Los Angeles and Chicago.

The five US consulates-general on the Chinese mainland are in Chengdu, Guangzhou, Shanghai, Shenyang and Wuhan. It also has a consulate-general for Hong Kong and Macao based in Hong Kong.

China reminded its citizens studying in the US to be on guard over arbitrary interrogation and detention by US law enforcement agencies as such cases have increased recently, the Foreign Ministry said on Wednesday.