GEC Plessey Telecommunications Ltd is concentrating its System X marketing efforts in the Comecon countries on Bulgaria following the relaxation of the trading restrictions on the exporting of digital technology by Western companies to the Eastern Bloc by the Co-ordinating Committee for Multilateral Export Controls on September 15. The company has applied to the UK Department of Trade & Industry for a trading licence, which will make it eligible to bid for the lucrative contracts sought by the Bulgarian government. Restrictions on exports remain however, albeit in a modified form. Exchanges must not exceed 50,000 subscriber lines or 13,000 trunk lines. Before the merger was effected, Plessey was negotiating the sale of System X in the Soviet Union, but its successor company says it is at present prepared to talk only about Bulgaria.