Joe Biden spoke on the US elections and warned about xenophobia during his Australia visit. (File Photo)

The "better angels in America will prevail" in the upcoming presidential elections, Vice President Joe Biden said as he warned about xenophobia during a visit to Australia.Biden said both the US and Australia were dealing with the legacies of racism and exclusion but would inexorably move forward."Don't worry about our election. The better angels in America will prevail," he assured Australians in Sydney at the end of his three-day visit."So at a time like this, when the forces of xenophobia and nationalism and demagoguery are once again being trumpeted around the world, including in my own country... we have to remember who we are as Australians and Americans and reflect our best selves back to the world."His comments came as Donald Trump was formally chosen by Republicans as the party's presidential nominee, despite relentless controversy over his campaign rhetoric.Trump has sparked international concerns with his call to build a wall on the US border with Mexico to keep out illegal migrants, for a ban on Muslim immigration, and for his suggestion that Japan and South Korea should develop nuclear weapons.Biden's trip Down Under also came days after an international tribunal ruled against China's claims in the South China Sea, and the vice-president sought to reassure the staunch American ally that the US would maintain a "laser focus" on the Asia Pacific region."I made the point, I've said to (Chinese) President Xi (Jinping) directly what I said to (Australian Prime Minister Malcolm) Turnbull yesterday, our resolve to play a part in shaping the future of this dynamic region is real," Biden added."We are not going anywhere. And that's vital because our presence in the region... is essential to maintaining peace and stability, without which the economic growth and prosperity I believe would falter."The US administration has called on China to respect international rules as Beijing asserts sovereignty over almost all of the strategically vital South China Sea, despite rival claims from its Southeast Asian neighbours.Biden next visits New Zealand, where he is due to meet with Prime Minister John Key for talks in Auckland.