In connection with the possibility of tightening up the blockade against Germany we have examined in consultation with the French authorities the measures open to us in respect of control of imports into Asiatic Russia. We have reason to believe that it will shortly be possible for Germany to develop the importation of deficient commodities of relatively high price and small bulk over the Trans-Siberian Railway and though we are ready to explore the possibilities that may offer, we feel unable to place any confidence in such assurances of non re-export as may be forthcoming from the Soviet Government.
The immediate action open to us appears to be:-
(a) the imposition of drastic restrictions on exports to Russia insofar as restrictions have not already been imposed;
(b) the interception and diversion for examination principally in Indo-Chinese ports of ships of all nations thought to be carrying cargo to suspected destinations.
We are taking immediate steps in regard to both of these courses of action.
As regards (b) orders have been sent to the Commander-in-Chief of the Chinese Station  to intercept ships if possible south of a line 21 degrees 21 minutes North, destined directly or indirectly for Vladivostock; Japanese ships from South East Asia are in no case to be intercepted north of this line and interception is not to be carried out within sight of the Japanese coast.
Similar instructions to the French Naval authorities have been given by the French Government.
It is hoped that insofar as restrictions do not already exist on exports to Russia of any goods important for prosecution of the War, His Majesty's Governments in the Dominions will be prepared to take similar measures to those being taken here. We should of course be ready to advise in any case of doubt.