The Russian aid convoy has moved across the Ukrainian border, without permission, after Russia accused Ukraine of obstructing it.
Russia’s foreign ministry said Ukraine had held up the convoy in order to pursue war against rebels in Luhansk, where the aid is destined.
The International Committee of the Red Cross (ICRC) said it was “not part of that convoy in any way”.
Reports suggest the trucks are being escorted by rebel fighters.
“Our humanitarian aid convoy is starting to move towards Luhansk,” the Russian foreign ministry said in a statement.
It warned Ukraine not to take any action against the convoy without specifying the consequences.
Ukraine fears that the aid convoy of at least 260 trucks, which arrived at the border more than a week ago, is part of a broader Russian intervention in eastern Ukraine.
Russia denies accusations that it arms and trains the rebels in the rebellion in Luhansk and the neighboring region of Donetsk, where four months of fighting have left more than 2,000 people dead and has caused more than 330,000 people to flee their homes.
The rebel-held city of Luhansk has been without running water, power and phone communications for 20 days as government forces hold it under siege.
As many as 70 trucks have entered Ukrainian territory, moving out of the no-man’s land between the Russian and Ukrainian border posts.
Reporters at the scene saw rebel fighters in front of the convoy as it passed over the border, in a rebel-held sector near the Russian town of Kamensk-Shakhtinsky.
It is normally a drive of about two hours from the trucks’ camp to the city of Luhansk.
However, it is unclear if the convoy will be able to use the motorway there because of continuing combat between rebels and government forces.
An ICRC spokesperson in Moscow said it had concluded that it had not “received the necessary security guarantees from the fighting parties to allow us to escort the convoy at this time”.
It cited “heavy shelling overnight” in Luhansk.
“We understand that the convoy is now moving, however the ICRC is not part of that convoy in any way,” the spokesperson added.
The Russian branch of the ICRC said earlier it was ready to take part in the relief operation and was contacting its international colleagues.
“We are warning against any attempts to sabotage this purely humanitarian mission, which was prepared a long time ago, in an atmosphere of full transparency and in co-operation with the Ukrainian side and the ICRC,” the Russian foreign ministry said.
Delays in Ukrainian clearance for the convoy had “become unbearable”, it said.
“All excuses for blocking the delivery of aid to people in the area where this humanitarian catastrophe is happening have been exhausted,” it added.
“The Russian side has decided to act. Our convoy carrying humanitarian aid is beginning to move towards Luhansk.”
There was no immediate comment on news of the convoy’s entry from the Ukrainian authorities.
Ukrainian media did report, however, that the convoy had not received the go-ahead from Ukraine.
In a statement on its website, Luhansk’s official council reported on August 22 that the dire situation in the city remained unchanged with no halt in the bombardment.
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