BBC business reporter

Stock markets in London, Paris and Berlin fell as trading began on Thursday after US President Donald Trump’s sweeping announcements on tariffs.
The UK’s FTSE 100 share index was down 1% while France’s Cac 40 fell 1.7%.
Earlier Asian markets had slid, while the price of gold, which is seen as a safer asset in times of turbulence, climbed to a record high.
Traders are concerned about the global economic impact of Trump’s tariffs, which they fear could stoke inflation and stall growth.
Markets across Asia had fallen sharply after Trump’s announcement, with the Nikkei in Japan closing down nearly 3% and Hong Kong’s Hang Seng index 1.5% lower.
The price of gold hit a record high of $3,167.57 an ounce at one point on Thursday, before falling back.
Futures markets also suggest US shares will open lower when trading begins later. The S&P 500 is indicated to fall by 3% and the Dow Jones by 2.4%.
The decision by the US government to impose a combination of a 10% baseline levy and higher duties on a number of other trading partners reverses decades of liberalisation that shaped the global trade order.
“This is the worst-case scenario,” said Jay Hatfield, chief executive at Infrastructure Capital Advisors.
“Enough to potentially send the US into a recession,” he added, echoing nervous market sentiment.
George Saravelos, head of FX at Deutsche Bank Research, said the new US trade tariffs were a “highly mechanical” reaction to trade deficits, rather than the “sophisticated assessment” the White House had promised.
Mr Saravelos warned the move “risks lowering the policy credibility of the [Trump] administration”.
“The market may question the extent to which a sufficiently structured planning process for major economic decisions is taking place. After all, this is the biggest trade policy shift from the US in a century,” he said.
Shares in sportswear firm Adidas fell more than 10%, while stocks in rival Puma tumbled more than 9% as key countries where their goods are made were hit with steep levies.
The new taxes include a 54% tariff on US imports from China and 46% on goods from Vietnam.
Among luxury goods firms, jewellery maker Pandora fell more than 12%, and LVMH (Louis Vuitton Moet Hennessy) fell more than 3% after tariffs were imposed on the European Union and Switzerland.
There are worries that the tariffs could affect US consumer spending which is a massive part of the global economy – between 10% and 15%, according to some economists’ estimates.