From [HERE] The UK High Court [official website]rejected [judgment, PDF] a "crime of aggression" allegation Monday against former UK Prime Minister Tony Blair [official website] by a former Iraq General Abdul Wahed Shannan Al Rabbat. The two justices dismissed the claim as UK law does not recognize a crime of aggression:

The existence of such difficulties cannot in any way justify the domestic courts of England and Wales departing from the clear principle that it is for Parliament to make such conduct criminal under domestic law. Parliament deliberately chose not to do so. The courts cannot usurp that function. It is for Parliament and Parliament alone to make the decision. Furthermore, there is no answer to the practical and constitutional difficulties identified by Lord Bingham and Lord Hoffman that would arise if a prosecution was brought without clear statutory provision.

The matter was dismissed before it could be brought to the Supreme Court for judicial review, the High Court determining that the highest court in Britain would not break away from its ruling in R v. Jones [judgment].

This ruling comes at the end of a long line of investigations into the Iraq War [JURIST backgrounder]. The Chilcot inquiry in July 2016 determined that the UK's entry into the Iraq War was not justified [JURIST report]. The same month the ICC determined that it would not prosecute [JURIST report] Tony Blair for crimes related to the Iraq War.