Most analysts believe that while the formal launch of the Brexit divorce process has symbolic significance for investors, the real driver for the pound will be how the negotiations with the EU play out and the health of the British economy going forward.

FTSE 100 extends losses

After a strong start to the day, the FTSE 100 slumped 0.3pc, with banking stocks among the biggest laggards, down 0.4pc.

In early trade, the blue chip index climbed by as much as 0.41pc to 7,373.62.

Meanwhile, the more domestically-focused FTSE 250 index extended its losses to 0.12pc following the formal start of the Brexit divorce process.

Although last year's EU referendum prompted an initial sharp sell-off in equities, the FTSE 100 quickly recovered, and is currently up 15.9pc from its pre-Brexit levels. Earlier this month, the FTSE 100 hit a record high of 7,447.00.

The blue chip enjoyed the stellar run as it is comprised of predominantly international, dollar-earning companies, who have received an accounting-related boost from the persistent pound weakness. The pound remains 16pc off its pre-Brexit levels.

Meanwhile, the FTSE Local UK index, which includes companies that generate more than 70pc of their revenues domestically, remains 0.96pc off its pre-Brexit levels.