Germany's financial capital, Frankfurt, climbed 32 places to seventh position, while Hamburg and Düsseldorf came in at 16 and 22, according to an annual index in British weekly The Economist.

Austrian leaders have taken part in a memorial service to remember the people killed during a shooting spree in central Vienna in 2020. Criticism remains over the government's actions in the run-up to the violence.

German officials said the raids were carried out in the homes of one German and one Kosovar national.

Music fills the Great Hall of Vienna's Musikverein once again, as the Philharmonic orchestra returns following months of lockdown that tested the musicians' motivation and turned their profession upside down.

Delegations from Washington and Tehran will be present at the talks, although direct contact is not on the table. The US has cautioned against high expectations.

Police say it's not clear how the shooter managed to get to Vienna's city center armed with an assault rifle, handgun, machete and fake explosive belt. They're also still looking into how the weapons reached Austria.

The Austrian government is calling for a system of international ethics on the use of killer robots and drones in combat. Vienna says it wants humans, and not algorithms, to decide on matters of life and death.

President Donald Trump's call for OPEC to keep oil flows unrestricted drew criticism from Saudi Arabia. The oil cartel convened in Vienna to discuss cutting output, in a bid to bring prices back from a two month slump.