China has taken the most active role among countries seeking to interfere in the United States election and has the biggest programme to influence domestic politics, US National Security Adviser Robert O'Brien said on Friday, without providing any details.
"We know the Chinese have taken the most active role," he told newsmen at a briefing, adding that China had "the most massive programme to influence the United States politically", followed by Iran and then Russia.
US intelligence found that Russia orchestrated a cyber campaign to sway the 2016 presidential election in Republican Donald Trump's favour and there have been reports that hackers may try to influence the election on Nov 3. Moscow has denied interfering in 2016.
"We've made it very clear to the Chinese, to the Russians, to the Iranians and others that haven't been publicly disclosed that anyone... that attempts to interfere with the American elections will face extraordinary implications," Mr O'Brien said.
Trump-appointed AttorneyGeneral William Barr said last Wednesday he believed China was more of a threat than Russia when it came to election interference, also without offering details.
The previous month, Mr O'Brien said the US had seen Chinese hackers targeting US election infrastructure. China has consistently denied US government charges that it hacks US firms, politicians or government agencies.
The Chinese Foreign Ministry has said Beijing has no interest in interfering in the US election.
Mr Trump has made getting tough on China a key part of his campaign for re-election as US president and blames China for the coronavirus pandemic.
In a speech to the Republican National Convention the previous month, he stated that Beijing supports his Democratic opponent Joe Biden and "desperately" wants him to win.
Asked to provide specific details of Chinese election interference, Mr O'Brien said: "I'm not going to go into all the intelligence, but the massive activities of the Chinese and cyber realm, it's really an extraordinary thing that we're facing."
Meanwhile, the Trump administration is considering whether to add China's top chipmaker, Semiconductor Manufacturing International Corp (SMIC) to a trade blacklist, a Defence Department official said on Friday, as the US escalates its crackdown on Chinese firms.
A Pentagon spokesman said that the Defence Department was working with other agencies to determine whether to make the move against SMIC, which would force US suppliers to seek a difficult-to-obtain licence before shipping to the company.
Earlier the previous week, the Pentagon made a proposal to place SMIC on the entity list to the End User Committee, a panel that makes decisions about entity listings, a person familiar with the matter said.
The Trump administration has often used the entity listwhich now includes more than 275 China-based firmsto hit key Chinese industries, from telecommunications equipment giants Huawei Technologies and ZTE over sanction violations, to surveillance camera maker Hikvision over suppression of China's Uighur minority.
SMIC is the largest Chinese chip manufacturer but is second-tier to rival Taiwan Semiconductor Manufacturing (TSMC), the industry's market leader. It's sought to build foundries for the manufacture of computer chips that can compete with TSMC.
But it's also facing new US restrictions that require Huawei's chip manufacturers to seek US licences before producing chips for the telecoms giant, if they rely on US chipmaking technology. SMIC is one of Huawei's manufacturers.
REUTERS