Washington, Oct 11 (IANS): NASA has been directed to reconsider applications of Chinese researchers who were banned from attending an upcoming planetary conference in California, said Charles Bolden, NASA administrator here.

Bolden was responding to a letter he received early this week from Frank Wolf, chairman of the House Appropriations sub-committee, who crafted a law in 2011 that prohibits government funds to be used for hosting Chinese nationals at NASA, reports Xinhua.

Wolf claimed in the letter that the law "primarily restricts bilateral, not multilateral meetings and activities" with the Chinese government or their companies.

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

In his response, Bolden said it is "unfortunate" that six Chinese participants were refused attendance at the Kepler conference, scheduled to take place at NASA's Ames Research Center next month.

Bolden said the applications will be reviewed once the US government reopens.

"Any of them applying and meeting the clearance requirements in place for foreign citizens will be accepted for participation in the conference," he added.

"The policies that led to their exclusion have had a negative impact on such scientific meeting. We strongly feel that it is wrong to exclude scientists on the basis of nationality for a meeting that welcomes free and open exchange of scientific ideas," the organisers said.