Russian humanitarian aid lorries which have entered Ukraine without permission constitute a Russian invasion of Ukraine, a flagrant violation of international law and a dangerous escalation of the situation. The trucks were part of a larger convoy that left the Moscow area last week, with Russia insisting that it be allowed to send aid to civilians - many of them Russian speakers - affected by the months of fighting in eastern Ukraine. The battles have left thousands without access to water, electricity and proper medical aid. But the true purpose of the aid convoy is not to support civilians but to resupply armed separatists. The Russian ruse is clever. Russia diverted 34 trucks from the aid convoy into eastern Ukraine after Russian and Ukrainian customs officials cleared them under the assumption that the International Committee of the Red Cross would be with them. But the Red Cross said it was no longer with the convoy because of the "volatile security situation," a reference to fighting between pro-Russian rebels and Ukrainian forces. This was a violation of the deal between the two countries that any humanitarian convoy must be monitored by the Red Cross. What Russia calls a humanitarian convoy into eastern Ukraine is a direct invasion under cover of the Red Cross, and part of a broader Russian intervention in eastern Ukraine. Ukrainian officials acknowledged that the convoy of more than 260 Russian vehicles was, in fact, carrying humanitarian aid. But it is the trucks that are important. They will probably be handed over to pro-Russian separatist militias, who have been fighting government troops since April, for use in the war. They will be used to transport equipment and weapons as part of a transport infrastructure which they lack. The presence of the trucks will certainly help Russia just as Ukrainian troops are advancing on the rebels' two city redoubts, Donetsk and Luhansk. The maneuver is potentially explosive because the Russian convoy has ventured into a part of eastern Ukraine where there is heavy fighting between government troops and pro-Russian rebels. Although Ukraine stated it was a "direct invasion", it also said no force would be used against the convoy as it wished to avoid "provocations". Yet, many things could still go wrong. If the trucks are fired upon – or if that is staged – then it could provide a pretext for a full-scale Russian invasion, something which Ukraine and the West have long feared. The separatists are also carrying out mortar attacks along the possible route of the lorries which are currently being accompanied by pro-Russian gunmen. In addition, because the Red Cross is not part of the convoy, the government in Kiev may ultimately choose not to recognize it as a humanitarian mission. Lastly, the Russian Foreign Ministry has already sent a clear warning that if the convoy is attacked, Moscow may take action. The trucks will reinforce Russia's 18,000 combat-ready troops on its border with Ukraine which Russia has stopped trying to hide. There has been a major escalation in Russian military involvement in the region over the past days, including direct artillery support both from across the border and within Ukraine, coinciding with a major escalation in Russian military involvement in Eastern Ukraine since mid-August, including the use of Russian forces. This is an alarming Russian build-up in the vicinity of Ukraine, an escalation which, with this latest direct invasion, has forced NATO for the first time to accuse Russia of directly intervening in Ukraine. Thus the risk of the Russian aid convoy causing a further deterioration in relations with Ukraine is now very high.