TRADE officials plan to step up their action on illegal transshipment once the computerisation of the department is completed and its textile export licensing system is in place by middle of this year. A Trade Department spokeswoman said shippers and forwarders would be obliged under the new licensing system to declare details of individual consignments of textiles and garments transshipped through Hongkong. At present they are exempt from standard licensing procedures. ''We are sure that the additional information available on the individual consignments of transshipped goods will greatly enhance our effectiveness in combatting illegal transshipments,'' said the spokeswoman. The department would not be lenient with those who deliberately flouted its control measures and brought the system into disrepute in the international trading community, she said. Repeat offenders risked suspension of registration and might even be disqualified from participating in the simplified licensing scheme and also denied other licensing facilities. Mr Leung Yau-yam, the Customs and Excise Department's head of trade controls, said the present legislation under the Import and Export Ordinance and Trade Descriptions Ordinance were adequate for the department to take action against offenders. Customs officers, he said, conducted periodic checks on factories and at the border to ensure the people in the trade met requirements under the various ordinances. The department prosecuted 839 cases connected to the origin of textiles involving $29.1 million in fines in 1991 and 940 cases involving $36.7 million in fines in 1992, Mr Leung said.