Representatives from 53 countries are descending on London for a meeting of Commonwealth nations. It will be a busy week for Prime Minister Malcolm Turnbull, who is also meeting with NATO and European Union officials.
Nobody hears much about the Commonwealth these days, outside of history books and the occasional Commonwealth Games.
But this week, (april 16-20) an unusual group of 53 countries will meet for diplomatic talks in London.
Australia's traditional Western allies will be there, but so will a range of African and Pacific nations all once occupied by the colonial British Empire.
While the Commonwealth is often described as old-fashioned and irrelevant, the Australian Strategic Policy Institute's Peter Jennings disagrees.
He says the biennial Commonwealth Heads of Government Meeting, or CHOGM, (CHOG-um) presents an excellent opportunity for a so-called middle power like Australia.
"CHOGM is particularly important for sort of the old Commonwealth -- Britain, Canada, New Zealand -- but it also gives us very good ties into Africa, which is a continent of future interest and a lot of Australian investment, so I think it's worth Turnbull's time."
There is a lot on the agenda for CHOGM, but one of the most controversial debates will centre on who should replace the Queen as the so-called Head of the Commonwealth.
Prince Charles is the rumoured favourite, but some countries are reportedly pushing for a democratic vote instead of simply continuing with the British monarchy.
The Royal Family will be well-represented at the talks, with the engaged couple Prince Harry and Meghan Markle attending various events.
For Australia, though, the meetings are particularly a chance to strengthen ties with Pacific nations, especially as China expands its military presence in the South China Sea.
The meeting comes amid reports of a planned future Chinese base on Vanuatu.
Mr Jennings says Australia has taken its influence in the Pacific for granted and has let rivals establish a footing.
"I think we've been, frankly, fooling ourselves for a couple of decades now that we have a leadership position in the Pacific, which we really don't have anymore. We've kind of lost a lot of those connections, particularly on the military side, where, for the last 12, 13 years, we've been heavily involved in Afghanistan and the Middle East and really taken our eye off the ball* as far as the Pacific is concerned."
Mr Turnbull will extend his European trip for meetings with the NATO, or North Atlantic Treaty Organisation, military alliance.
Those meetings will focus on the recent tension with Russia, which United States president Donald Trump now says is worse than during the Cold War.
Hundreds of Russian diplomats were recently kicked out of embassies in Western nations over the poisoning of a former double agent in Britain.
The Commonwealth nations will also talk cybersecurity and counterterrorism.
But Malcolm Turnbull is pursuing economic ambitions, too, and plans to meet with leaders of the European Union.
Mr Turnbull arrives in London on Wednesday. (april 18)
