Japan's defence minister is jetting off to Canberra this week for the highest-level engagement with Australia since a controversy involving melons, hand gestures, and a prime minister who may or may not have been making a breast joke. Shinjiro Koizumi, the defence minister and a man with a famous dad, will meet his counterpart Richard Marles on Tuesday to talk about Australia's purchase of Japan's Mogami-class frigates and other security cooperation. Because nothing says 'serious diplomatic relations' like a fruit-based misunderstanding.

Koizumi, who is considered a potential future prime minister, is the son of Junichiro Koizumi, who ran the show from 2001 to 2006. He's making this trip after a week in which Australian PM Anthony Albanese had to defend himself over comments made on the Bush Deep podcast, released last month. While discussing a pair of Japanese melons gifted by Prime Minister Sanae Takaichi during her visit to Canberra earlier this year, Albanese made some hand gestures near his chest and said, 'she brought two, as you do.' Host Nikki Osborne then quipped, 'She came in looking like Pamela Anderson.'

Cue days of criticism from the opposition and media, with Albanese insisting his gestures and comment were misinterpreted and were not innuendo about breasts. The opposition cried foul, suggesting he'd jeopardised relations with a key Asian partner. Japan's ambassador to Australia, Kazuhiro Suzuki, eventually released a statement that didn't raise any further issue, noting Takaichi's visit in May and how Albanese had hosted her for dinner 'in a very relaxed atmosphere,' which apparently built personal trust. A leaked diplomatic cable from July blamed 'sensationalised reporting in the Australian media' and said Tokyo saw no 'ill intention' in Albanese's actions.

Albanese had already apologised for comments about Kylie Minogue made in the same podcast, because why not pile on? Koizumi's visit is part of a five-day trip that includes a stop in India. Marles told Guardian Australia, 'Our relationship with Japan continues to go from strength to strength, and I look forward to welcoming my good friend, minister Koizumi back to Australia this week.' He added they'd discuss co-developing and co-producing defence capabilities, advanced weapons testing, enhanced training, and intelligence cooperation.

Meanwhile, Takaichi faces her own headaches, with sliding poll numbers and cost-of-living issues. And Koizumi got scolded by China over the weekend for visiting the Yasukuni Shrine, which is always a crowd-pleaser with Japan's neighbours. In August last year, Australia agreed to buy three of Japan's Mogami-class frigates for $10bn over a decade, with the first expected in December 2029. So, all in all, a perfectly normal week in international diplomacy, where melons and hand gestures almost caused a kerfuffle.