WASHINGTON (Reuters) - Secretary of State Antony Blinken on Wednesday singled out the U.S. relationship with China as the main overseas focus of President Joe Biden’s administration and said the country posed “the biggest geopolitical test” of this century. In a speech at the State Department, Blinken sought to set out how foreign policy will bring benefits for American workers and families, and said that was key to the new administration’s approach. Biden wants to signal a break with former President Donald Trump’s “America First” approach by re-engaging with allies and centering multilateral diplomacy, while also recognizing the world has changed since he served in the Obama administration that preceded Trump. “We will fight for every American job and for the rights, protections and interests of all American workers,” Blinken said. China was the only nation Blinken said was one of eight priorities, which also included working to avoid another global pandemic, tackling climate change and promoting democracy abroad. China is the only country with the power to seriously challenge the U.S. ability to shape the global system of “rules, values and relationships,” he said. “Our relationship with China will be competitive when it should be, collaborative when it can be, and adversarial when it must be,” Blinken said. The world’s two most powerful nations are at odds over influence in the Indo-Pacific region, Beijing’s economic practices, Hong Kong, Taiwan and human rights in China’s Xinjiang region. Biden has called Beijing the “most serious competitor” for the United States and his administration has indicated it will broadly continue a tough approach to China taken by Trump. Engaging with China “from a position of strength,” as the administration seeks to do, “requires standing up for our values when human rights are abused in Xinjiang or when democracy is trampled in Hong Kong, because if we don’t, China will act with even greater impunity,” Blinken said. Blinken has said he agrees with his predecessor Mike Pompeo’s determination that genocide against Muslims is underway in Xinjiang, but did not use the term in his speech. Activists and U.N. experts say 1 million Muslim Uighurs are held in Chinese camps. China denies abuses and says its camps provide vocational training and are needed to fight extremism.