Prince William will be wearing the uniform of a "conqueror" when he arrives in the Falklands on his deployment as an RAF search-and-rescue pilot, Argentina has said.
The barb came with tensions running high over the disputed islands, which Buenos Aires calls Las Malvinas.
Amid increasing tensions ahead of the 30th anniversary of the Falklands War, it emerged On Tuesday that one of the Royal Navy's most advanced new warships was also being sent to the area.
HMS Dauntless, a Type 45 destroyer , is due to set sail for the South Atlantic on her maiden mission in the coming months to replace frigate HMS Montrose.
A Royal Navy spokesman denied there was anything sinister behind the move.
"The Royal Navy has had a continuous presence in the South Atlantic for many years," he said.
"The deployment of HMS Dauntless to the South Atlantic has been long planned, is entirely routine and replaces another ship on patrol."
Referring to HMS Dauntless and the Duke of Cambridge's tour of duty, Argentina's Foreign Ministry said it "rejected the British attempt to militarise (the) conflict".
It also expressed regret that an heir to the throne would arrive wearing "the uniform of a conqueror and not with the wisdom of a statesman who works for peace and dialogue between nations".
The war of words has previously seen David Cameron and Argentine president Cristina Fernandez accuse each other of "colonial" behaviour.
William, a Flight Lieutenant with the RAF, will deploy to the remote outcrop in the South Atlantic for six weeks.
But the Chief of the Defence Staff has dismissed claims that sending the Duke to the Falkland Islands was designed to provoke Argentina.
"I can absolutely tell you it wasn't and isn't designed to be," said General Sir David Richards.
Gen Richards stressed William's deployment was routine for an RAF Sea King pilot, pointing out that Prince Harry was sent to Afghanistan as a forward air controller in 2008.
Meanwhile, Harry's private secretary has insisted that William's younger brother's visit to Argentina's neighbour Brazil will not inflame tensions.
"I'm confident this issue will not flare up when he arrives in Brazil," Jamie Lowther-Pinkerton told journalists at a St James' Palace briefing.
Brazil is a member of the Mercosur trade group, which turns away vessels flying the Falklands flag from its ports.
It has also emerged foreign minister Jeremy Browne will be visiting the islands in June to coincide with the anniversary of the Falklands War.
Argentina's ruling military invaded the islands on April 2, 1982, beginning a 74-day war that left 649 Argentine and 255 British troops dead.
:: Prince's visit stirs up tensions with Buenos Aires