Grand Duke George Mikhailovich Romanov, 40, and his Italian fiance Rebecca Virginia Bettarini, 39, were preparing to say their vows at Saint Isaac's cathedral in the former imperial capital Saint Petersburg in the presence of dozens of European royals.

On the return flight to Turkey from the talks, Erdogan told reporters he also proposed working with Russia on construction of two more nuclear power plants, and Putin suggested developing platforms for space rocket launches, broadcaster NTV reported.

In a dozen countries with high vaccination rates in Asia, Europe and the United States, case rates that surged in August have mostly fallen back, according to local data and officials.

The threat against Rutte, who is known for riding his bike around town with little security, comes after the Dutch government pledged a crackdown on organised crime groups following the murder of a prominent investigative reporter in August.

The Petrol Retailers Association claimed that almost half of the UK's 8,000 fuel pumps had run out of petrol on Sunday, as desperate drivers formed long queues to fill up tanks.

The preliminary results are based on ballots counted in all constituencies. The result is the worst yet for Merkel's CDU-CSU bloc. 

The epochal election ushers in the end of 16 years in power for Merkel and places Germany, a byword for stability, in a new period of uncertainty.

In a joint statement issued after US President Joe Biden and French President Emmanuel Macron spoke by telephone for 30 minutes, the two leaders agreed to launch in-depth consultations to rebuild trust, and to meet in Europe at the end of October.

Instead, he can expect a warm welcome in Washington on Tuesday, as the trans-Atlantic leaders meet for wide-ranging talks intended to deepen ties that are expected to focus on security, climate and economic regulation in the run-up to Britain hosting a major environmental conference at the end of October.

"We are very, very proud of our relationship with France", Johnson told reporters on his way to New York, according to the report. "Our love of France is ineradicable."

French President Emmanuel Macron on Friday recalled the ambassadors to Canberra and Washington in an unprecedented move to signal his fury over Australia's decision to break a deal for the French submarines in favour of American nuclear-powered vessels.

The Prince's Foundation said chief executive Michael Fawcett had agreed to suspend his duties pending an internal investigation into the allegations by The Sunday Times and Mail on Sunday.

"Last week, there was an 11 percent increase in the number of deaths in the region –- one reliable projection is expecting 236,000 deaths in Europe, by December 1," WHO Europe director Hans Kluge told reporters.