The Prince of Wales and the Duchess of Cornwall have been a hit in Papua New Guinea, Australia and New Zealand – except with one Kiwi, Sam Bracanov, who tried to throw a bucket of horse manure over them.

Mr Bracanov, 76, had it all carefully planned. He had gone out and bought a bag of manure for NZ$2. He had mixed it with water, to "make it liquid, like a porridge", he explained outside Auckland District Court yesterday. Then he travelled, armed with the bucket, to the Auckland quayside area, where the royal couple were due to meet well-wishers on Monday, arriving well before them.

It was at that point that Yugoslavia-born Mr Bracanov – described by police as "a known anti-royalist" – was swooped on and arrested. In court, he pleaded not guilty to a charge of preparing to commit a crime in a public place. Moments later, seated on an upturned rubbish bin outside court, he told reporters: "I would have done it."

Mr Bracanov – remanded on bail on condition that he remains 500 metres away from Prince Charles and Camilla, who are touring New Zealand – has "form", as police might say. During a previous visit to New Zealand by Charles in 1994, he was fined for spraying air fresheners at the Prince – to "remove the stink of royalty", he explained later.

This time, he was attempting to register a protest at Charles's privileged position, he said. "He didn't qualify with his brain, he qualified with his body, and what [the] body produce[s] goes to toilet, so I would hit him with what goes to toilet."

Otherwise, the couple's Pacific tour – marking the Queen's Diamond Jubilee – has gone well, particularly in Australia, where republicans brandished the spectre of "King Charles III and Queen Camilla" in an attempt to persuade Australians to ditch the monarchy in a failed referendum in 1999.

One leading republican, the author Thomas Keneally, admitted last week end that the tactic had been misjudged. Mr Keneally, who met Camilla in London just before the couple departed for the Pacific, told The Australian she was "absolutely charming".

In Australia last week, the couple cuddled koalas in Adelaide, visited a sheep stud in Tasmania and supped from a A$4,000 bottle of South Australian red. They also attended the Melbourne Cup horse race, where Camilla presented the trophy to Nick Williams, the son of the owner of Green Moon, the winning horse.

If Australia has warmed to Charles and Camilla, the opposite might also be true. It was, after all, an Australian magazine, New Idea, which in 1993 published the infamous "tampon tapes", the transcript of a telephone conversation between Charles, then married to Diana, Princess of Wales, and Camilla, then married to Andrew Parker Bowles.

Now they're respectably married to each other, and in New Zealand, Charles and Camilla received the obligatory Maori greeting of a hongi, or nose rubbing, before glad-handing the crowds. Today the Prince will celebrate his birthday with a visit to the Wellington studio of Peter Jackson, who is putting the finishing touches to his trilogy of Hobbit films.