Six Chinese scientists who were banned from a NASA astronomy conference are now welcome to register, resolving an international row over academic discrimination, a co-organizer told AFP on Monday.

The US space agency ban on allowing the scientists to enter a NASA building for the meeting next month prompted a boycott by some prominent American astronomers and was described as discriminatory by Beijing.

The matter was resolved once the 16-day US government shutdown ended and NASA corrected what administrator Charles Bolden said was a misconception among some agency managers that recent US legislation prevented Chinese nationals from entering space agency premises.

"We have since been able to clarify the intent of the referenced legislation and are pleased to inform you that this decision has been reversed and your paperwork is being reviewed for clearance," a NASA committee wrote to the six scientists, according to Alan Boss, a conference organizer.

"We hope you will be able to join us," it added.

The conference on distant planets discovered by NASA's Kepler project is to be held November 4-8 at a US space agency facility in northern California.

"As far as I know, all the problems of the last three weeks in this regard have been solved, now that the federal shutdown is over and NASA is back to work," Boss said.

The initial decision to block the six led to an academic uproar and plans to boycott by some leading US astronomers, including Yale University's Debra Fischer and Geoff Marcy, an astronomy professor at the University of California, Berkeley.

"The meeting is about planets located trillions of miles away, with no national security implications," Marcy wrote in an email to organizers.

China's foreign ministry also blasted NASA's denial of the researchers' applications as discriminatory, arguing that politics should have no place at academic meetings.

Bolden responded earlier this month by pledging to review the committee's decision, which he blamed on "mid-level managers" at the agency's Ames Research Center, which is hosting the event.

Ninety-seven percent of NASA staff were sent home without pay due to the partial US government shutdown earlier this month after Congress failed to pass a budget in time.

The ban was initially blamed by conference organizers on a 2011 law authored by Congressman Frank Wolf, who has described the Chinese government as "fundamentally corrupt," and has pushed for limits to US ties with China over concerns about human rights abuses, espionage and cyber attacks.

Since then, the "Wolf clause", as the provision has come to be known, has led to a number of decisions that have incensed the Chinese government.

For instance, in May 2011, when the US space shuttle Endeavour blasted off from Florida's Kennedy Space Center for its final space mission, two Xinhua journalists were barred from covering the event.

In an editorial at the time, Xinhua wrote that the provision penned by Wolf "exposed the anxiety of hawkish politicians in the United States over China's peaceful development in recent years, and it also demonstrated their shortsightedness to the whole world."

Wolf urged NASA to reverse course on its latest ban, saying the provision only restricts US space cooperation with China's government and Chinese companies, but not individuals.