This was a question I was asked recently by a delegate on our Compelling Bid course and this was the explanation provided.
The abbreviation stands for Voluntary Ex-Ante Transparency notice and it is covered by the Remedies Directive.
It is a means of advertising the intention to let a contract without opening it up to formal competition. A contracting authority may decide that a contract does not require prior publication through a contract notice in the O.J.E.U. A reason for this decision may be that the contract meets the exceptional conditions described in Article 31 of Directive 2004/18/EC. In a recent V.E.A.T notice the reason was listed as “extreme urgency brought about by events unforeseeable by the contracting entity and in accordance with the strict conditions stated in the Directive” .
If a contracting authority decides to take this route, they must give sufficient information as to the justification for direct award and they must still observe the minimum standstill period. By doing this it provides economic operators the opportunity to challenge the decision.