BRUSSELS (Reuters) - U.S. Secretary of State Antony Blinken said on Thursday that cooperation between allies was more important than at any time in recent history and that relations with NATO and the European Union would be crucial to overcoming challenges. Speaking on the last day of his three-day visit to Brussels, Blinken continued what many European officials said was a charm offensive to win back the support of allies sidelined during four abrasive years under U.S. President Joe Biden’s predecessor Donald Trump. “I came here very much with one particular focus in mind, and that was to make clear the United States’ determination to revitalise our alliances and partnerships,” Blinken said alongside Belgium’s Foreign Minister Sophie Wilmes. He later told U.S. diplomats in Brussels he wanted to mend and “modernise” relationships to focus on new challenges, which he has listed as China’s rise, COVID-19, climate change, a newly assertive Russia and keeping a technological edge on rivals. “There’s a greater premium than any time since I’ve been involved in these issues, on finding ways to work together, again,” said Blinken, a long-time Biden confidant involved in U.S. foreign policy for decades. Blinken won European Union support on Wednesday for a U.S. plan to confront Chinese power together through a formal dialogue that Beijing had hoped to avoid, praising EU officials who Trump actively sought to undermine. “A basic tenet of the Biden-Harris administration is consulting with our friends, early and often,” Blinken said. Biden will address EU leaders via video conference later on Thursday, the first such gesture since President Barack Obama did so in 2009. Issues remain, however, including Turkey’s purchase of Russian missiles and discussions with Moscow to buy more, and the Nord Stream 2 pipeline under construction between Russia and Germany, which Blinken reiterated that Washington opposes. Slideshow ( 2 images ) “Some of our allies are moving in the wrong direction,” he said on Wednesday, referring to backsliding on democracy in Hungary, Poland and Turkey, although he did not name countries. He stressed that alliances need to serve U.S. interests and that NATO allies must help pay for their own security, saying: “We can’t sustain effective alliances without showing how they deliver for the American people.” But China’s decision on Monday to retaliate strongly against Western sanctions over human rights abuses has appeared to bring Europe and the United States closer together. European governments have summoned Chinese envoys to explain measures against EU nationals that were seen as going far beyond what Brussels imposed. “We’re convinced that it is (through) enduring relationships, like the one between our countries, and like the ones that exist through the European Union and through NATO ... that we can overcome any of these challenges,” Blinken said. Citing the “devastating” COVID-19 pandemic, Blinken promised to work with the EU and NATO on global distribution of vaccines, and to ensure they are prepared for future pandemics. While insisting Europe does not have to choose between the United States and China, Blinken insisted throughout his trip that the West must show authoritarian states that democracy is a superior system and stand up for liberal values.