Image caption The conference on Nasa's Kepler space telescope programme is an important academic event for scientists who work in the field

The US space agency has said it will allow Chinese scientists to attend an astronomy conference in California next month, reversing an earlier ban.

Nasa put the earlier ban down to a misinterpretation of its policy on foreign nationals.

Chinese officials had called the rejection of Chinese scientists' applications a form of discrimination.

The event for scientists who research planets beyond the solar system will be held at Ames Research Center.

The bar on Chinese scientists, revealed earlier this month, was prompted by new counter-espionage legislation restricting foreign nationals' access to Nasa facilities, Nasa spokesman Allard Beutel told the BBC.

The conference will be attended by US and international researchers who work on Nasa's Kepler space telescope programme.

'Misinterpretation'

The agency faced criticism from Chinese officials and US scientists who claimed Chinese students and researchers in their labs were being subjected to discrimination.

In recent weeks, a growing number of US scientists decided to boycott the meeting in protest, with senior researchers withdrawing individually or pulling out their entire research groups.

"The initial decision was based on a misinterpretation of the agency's policy regarding foreign nationals," Mr Beutel said.

"We were able to clarify that interpretation and correct the decision, but it didn't happen until the federal government reopened last Thursday."

Earlier this month the US government partially shut down operations for 16 days, putting hundreds of thousands of federal employees on leave.

The counter-espionage legislation passed in March was part of a broad and aggressive move initiated by Congressman Frank Wolf, Republican chairman of the House of Representatives subcommittee that has jurisdiction over Nasa's budget.

Mr Wolf later called Nasa's reading of the legislation "inaccurate" and sought to clarify the original intent of the law.

"The congressional provision - which has been in place since early 2011 - primarily restricts bilateral, not multilateral, meetings and activities with the Communist Chinese government or Chinese-owned companies," Mr Wolf wrote in an 8 October letter to Nasa Administrator Charles Bolden.

"It places no restrictions on activities involving individual Chinese nationals unless those nationals are acting as official representatives of the Chinese government," he wrote.