Rising tensions between the United States and China could derail the renewal of a 44-year-old agreement on scientific cooperation between the two countries.

Last week, U.S. President Joe Biden invited China to spend the next 6 months discussing changes to the broad agreement, first signed in 1979, that enables joint research. The move came after Biden rejected calls from some Republicans to let the pact lapse on 27 August, its planned expiration date.

But the 6-month extension leaves little time to resolve a host of thorny issues, policy experts say. They include how to protect intellectual property rights to any findings, share data among collaborators, and ensure that research outcomes are fully reported. The Biden administration also faces calls to block joint work on any technologies that could have both civilian and military applications.

Chinese officials welcomed the extension. “As two major R&D countries, China and the United States should maintain contact and exchanges” in science and technology (S&T), Chinese embassy spokesperson Liu Pengyu said in a statement to Science. The pact’s history “has fully proved that China-U.S. exchanges and cooperation are mutually beneficial,” he said.

Prominent U.S. scientists also applauded Biden’s move. “This agreement has been of enormous benefit to the United States,” wrote Stanford University physicists Steven Kivelson and Peter Michelson in a letter to Biden signed by more than 1000 scholars before the extension was announced. “We can attest that cutting off ties with China would directly and negatively impact our own research, the work of our immediate colleagues, and the educational mission of our universities.”

The pact, which has undergone revisions across several 5-year renewals, essentially says “that it’s OK with the U.S. government that [U.S. researchers] collaborate on science and technology with China, with appropriate selectivity and management,” says physicist John Holdren of Harvard University, who served as science adviser to former President Barack Obama and helped negotiate an extension in 2011.

The U.S. has similar bilateral research agreements with some 60 countries. The one with China, commonly known as the Science and Technology Agreement (STA), neither provides funding for joint projects nor mandates research in any particular sector. But it enables government agencies, universities, companies, and other entities in each nation to pursue joint research. Such projects have included a landmark clinical study showing how folic acid can prevent birth defects and a network of clean energy research centers.

“It is particularly important, at a time of tension in so many dimensions of our relationship with China, that we show that there are things worth preserving in that relationship,” Holdren says.

Congressional Republicans and others, however, say collaborating with China poses a major threat to U.S. economic and national security. “The Chinese Communist Party has abused the openness of the American scientific community to steal American research and coopt it for its own malign purposes,” Representative Mike Gallagher (R–WI), chair of the Select Committee on China in the U.S. House of Representatives, said after the extension was announced. Two months ago, Gallagher and nine Republican colleagues wrote Secretary of State Antony Blinken urging him to let the agreement lapse.

No STA project has involved sensitive or classified research. But even fundamental research discoveries can help China gain an advantage over the U.S., Gallagher asserted. “The evidence available suggests that [China] will continue to look for opportunities to exploit partnerships organized under the STA to advance its military objectives,” the letter argues. “The United States must stop fueling its own destruction.”

The STA holds symbolic significance for China because it was the first agreement the two countries signed after normalizing relations in 1972, says Huiyao Wang, president of the Center for China and Globalization, a Beijing-based think tank. It was renewed during the most tumultuous times, such as after the 1989 massacre at Tiananmen Square. Even the administration of former President Donald Trump, which was no fan of China, agreed to several short-term extensions before signing the current STA, which added language to protect intellectual property, in 2018.

Since the Biden administration took office in January 2021, it has not launched any new government-to-government initiatives under the STA. Although ending the bilateral agreement wouldn’t prevent government-to-government scientific cooperation, a U.S. Department of State spokesperson says, “each agency would have to negotiate arrangements for each individual cooperation.”

Gallagher’s letter to Blinken turned what had been quiet negotiations between the two sides into a front-burner political issue. Ending all collaboration because some future project might become problematic would amount to “throwing the baby out with the bathwater,” says Holdren, who hopes the two sides can reach an agreement. Even so, supporters of a new deal say changes are needed.

“I’d like to see language relating to greater transparency and data sharing,” says Sudip Parikh, CEO of AAAS (which publishes Science), citing the potential value of pooling health or environmental data collected by each country. “Reciprocity has not always been a hallmark of China’s scientific enterprise.”

The pact should include “some kind of free flow of information requirement,” says Denis Simon, an independent specialist on China policy. He notes that ambiguous wording in recent Chinese data protection laws has left foreign scientists unsure that they will have access to data generated by joint projects.

China may be skeptical of any proposed changes. “If the U.S. is thinking about improving and strengthening this agreement,” a deal is within reach, Wang says. But if the U.S. wants to limit the pact or add inequitable clauses, he warns, “that could be a problem.”

The issue’s politicization is already hindering cooperation, says Mu-ming Poo, head of the Chinese Academy of Sciences’s Institute of Neuroscience.  Renewing the STA “is helpful only if there is basic trust and true willingness to collaborate,” says Poo, who spent decades in the U.S. before returning to China.

U.S. officials acknowledge that striking a new deal won’t be easy. “We are clear-eyed about the challenges associated with [China’s] national strategies related to S&T, as well as its domestic legal framework,” the State Department spokesperson said. “Strengthened protections in the agreement will be essential for any longer-term extension.”

If a deal can be reached, Holdren predicts the Biden administration will take advantage of it to launch several joint projects. Areas ripe for collaboration, he says, include efforts to prevent future pandemics, improve nuclear reactor safety, and better monitor earthquake activity.