European stocks closed in the green on Tuesday, with French shares among the biggest advancers as eurozone economic activity remained at a six-year high. But travel-related shares edged lower following a suspected terror attack by a suicide bomber in Manchester, England, which killed 22 people, including children, and injured 59 as people left an Ariana Grande concert on Monday night.

U.S. stock-index benchmarks closed higher Tuesday, marking a fourth straight session in the green following the White House's release of its 2018 budget proposal. The moves come amid mixed economic data and an updraft in shares of financial firms.

China's main stock index fell one percent and the Australian dollar slipped on Wednesday after Moody's cut its sovereign credit rating on China. Moody's said growing leverage in China prompted the downgrade, and warned about slowing economic growth. China's massive debt been at the center of concerns among economists and Beijing in recent months, and has rattled global financial markets since late last year.