Beijing must honour implementation of an international ban on prison-made exports, a senior American official says. US Treasury Secretary Robert Rubin yesterday challenged Communist Party authorities to honour a 1994 pact that allows American inspectors to verify that goods produced for sale overseas are not made with forced labour. 'It certainly is a difficult issue,' Mr Rubin said. Dissidents and human rights groups allege mainland prisoners have been forced to produce toys, Christmas lights, T-shirts, shoes, footballs and other goods for export - charges Beijing dismisses as 'entirely groundless'. Mr Rubin said he raised 'sporadic implementation' of the pact in private talks with Ministry of Finance officials in Beijing. 'We need to look at it again to see if we can make implementation more effective,' he said, adding he felt progress had been made. Under its treaty with Washington, China agreed to allow prompt probes of violations by US officials. The US Customs Service has accused the mainland of repeatedly ignoring requests for information. At a Joint Economic Committee summit in Beijing yesterday, US and mainland authorities pledged to strengthen co-operation in abolishing prison exports.