The merits of using ships to deport boat people have been detailed in confidential reports to Hong Kong refugee officials and the British Foreign Office.
While falling short of directly advising sea repatriations from Hong Kong, the reports focus on the success of a Malaysian operation last week which saw 317 Vietnamese returned to southern Vietnam using a Malaysian Navy landing craft.
It is understood Hong Kong, which has in the past rejected the use of sea transport, is now looking at the proposition afresh.
In 1993, the Government was offered passenger ferries by China Merchants (Holdings) Ltd, a large mainland-owned shipping company, to ferry ex-China Vietnamese illegal immigrants back to the mainland. The proposal was eventually rejected.
With 18,000 boat people left in the territory and the 1997 handover looming as the deadline for clearance, Hong Kong has begun increasing the number of flights, but has had difficulties in securing aircraft.
A diplomatic source said the sea option was being considered by Hong Kong following the smooth operation from Malaysia last week.
