UK Deputy Prime Minister Nick Clegg came under fire Wednesday after he declared the 2003 invasion of Iraq was illegal, during a House of Commons debate.

Standing in for Prime Minister David Cameron who is visiting Washington, Clegg became involved in a heated exchange with Jack Straw, shadow minister of justice for the opposition Labour Party, who was UK foreign minister at the time of the invasion of Iraq.

"We may have to wait for his [Straw's] memoirs, but perhaps one day he will account for his role in the most disastrous decision of all: the illegal invasion of Iraq," Clegg said.

Commentators seized on Clegg's statement as a sign of political division in the UK government, a coalition between the Conservative and Liberal Democrat Parties. In 2003 the Liberal Democrats voted against the House of Commons motion authorizing the invasion of Iraq, while the Conservatives, including David Cameron, voted in favor.

Perhaps more importantly, lawyers argued that Clegg's statement increased the likelihood of charges being laid against Britain and the British armed forces, in international courts.

The UK Guardian quoted Philippe Sands, professor of law at University College London, as saying: "A public statement by a government minister in parliament as to the legal situation would be a statement that an international court would be interested in, in forming a view as to whether or not the war was lawful."

The fact that Clegg was deputizing for David Cameron, and effectively speaking as the UK head of government when he made the remarks, increased the likelihood his statement could have legal consequences.