The crisis in Ukraine cast a shadow over Chinese efforts to mark the 50th anniversary of an important milestone in its relationship with the United States as a former American official warned that ties would worsen if Beijing maintains its current position . “Fifty years ago, the USSR was a common threat that brought us together. Today, Russian aggression threatens to drive us further apart,” former US treasury secretary Jacob Lew said in an online speech to an event to mark the signing of the Shanghai Communique, which paved the way for the establishment of formal relations . Beijing urges US to learn from Nixon’s historic visit “This is the moment when nations of the world respecting international order are joining together condemning Russia’s illegal attack on Ukraine,” said Lew, now the chair of the board of directors at the National Committee on US-China relation s, a non-profit organisation. “China must decide where to stand and understand that the bilateral relationship with the US will only become more strained in the absence of a clear choice to stand with intervention.” Monday’s event was hosted by the semi-official Chinese People’s Association for Friendship with Foreign Countries and the Shanghai municipal government to commemorate the 50th anniversary of the communique, signed at the end of president Richard Nixon’s visit to China in 1972 . Those attending the event included a number of senior Chinese officials, including Foreign Minister Wang Yi, Shanghai Communist Party chief Li Qiang and Qin Gang, the ambassador to Washington. But no incumbent US official spoke at the event, though the chargé d’affaires at the US embassy David Meale was there. The event was held amid the worst US-China relation s in decades and days after the Russia invasion of Ukraine. China, along with India and the United Arab Emirates, abstained in a UN Security Council vote on Friday on a resolution to condemn Russia’s attack on Ukraine. On Monday, officials from the Chinese side largely bypassed the topic and focused on the Taiwan issue , which Wang described as the biggest sticking point in the relationship with the US. Wang said “the principles and spirit established by the Shanghai Communique … have not been truly followed”. In a pre-recorded speech, Wang said US commitments to Taiwan, including commitments to help the island defend itself, contradicted its commitment to the one-China principle set out in the 1972 agreement. Winston Lord, in the room with Mao and Nixon, on US-China relations then and now The US “acknowledges” Beijing’s stance that there is only one China and that Taiwan is part of it. Wang also said China was willing to work with the US on the Build Back Better World, a G7-led global infrastructure plan, and would welcome Washington joining its Belt and Road Initiative . Former Chinese ambassador to the US Cui Tianka said he believed the Shanghai Communique remained relevant on issues including “Nato expansion”. There is no direct mention of North Atlantic Treaty Organisation in the communique, which affirmed that neither nation “should seek hegemony in the Asia-Pacific region and each is opposed to efforts by any country or group of countries to establish such hegemony”. Another event planned for Fudan University in Shanghai on Sunday has been postponed because of concerns about Covid-19. Monday’s event stood in contrast to when the two countries celebrated the event at its 40th anniversary in 2012, when Chinese President Xi Jinping, then vice-president, was the highest level official at a ceremony in Beijing, where he welcomed Henry Kissinger, who played a key role in the Nixon administration’s visit to China. Kissinger, who sent a pre-recorded speech to the event on Monday, said it was inevitable there would be disagreements between the two countries over some issues. “But what we should learn from the past and what I hope we can project into the future is that we maintain a permanent dialogue and that we tell each other frankly what our thinking is on key issues, and that we should do that with an attitude that in the world of modern technology, pressure and military threats, we will not do anything that threatens the two halves of humanity.” He added that the development of “great technology” by both sides would have threatening aspects that “must be discussed to be kept limited or removed”.