By Sara Sjolin, MarketWatch

U.K. high court rules government can't trigger Brexit process without approval from parliament

The pound leapt and added pressure on U.K. stocks on Thursday after a high court ruled the government can't trigger the Brexit process without signoff from parliament.

The FTSE 100 index dropped 0.5% to 6,814.21, after trading as high as 6,873.21 earlier in the session.

The benchmark fell after the government was dealt a major blow to its Brexit plans (, with a high court saying Prime Minister Theresa May does not alone have the power to trigger the so-called Article50 that kicks off negotiations with the European Union. That means she must put it up for a vote in parliament.

The government has said it would appeal the verdict.

See also: Brexit ruling: 5 things you need to know (

"While the ruling may be reversed when appealed at the start of December, the decision does offer hope to 'remainers' that the triggering of article 50 will be delayed, but in the best case scenario, it won't pass through parliament and the Brexit referendum will have been for nothing," said Craig Erlam, senior market analyst at Oanda, in a note.

Read:'Fresh battle over Brexit' -- analysts react to U.K. high court ruling (

The pound jumped after the decision, hitting an intraday high of $1.2495, the highest in almost a month. Sterling got an extra boost around lunchtime from the Bank of England's decision to keep rates on hold ( make no changes to its quantitative easing program. The central bank also signaled it won't cut rates this year, with Gov. Mark Carney saying the BOE now has a "neutral" policy bias.

A strong pound tends to weigh on the FTSE 100 because of the index's many export-dependent companies that benefit from a weaker currency.

The more domestically focused FTSE 250 that benefits from a stronger currency rallied 0.9% to 17,615.61 on Thursday.

"If the British currency can maintain this momentum -- and the Bank of England will have a great influence here -- then investors may need to reassess their clear preference for dollar earners and exporters and begin to look at downtrodden domestic plays once more," said Russ Mould, investment director at AJ Bell,in a note.

Sterling has sold off in recent months on fears the government was heading for a so-called hard Brexit that was seen as hurting the financial industry and slowing economic growth. However, analysts said Thursday's court ruling could soften the Brexit talks and potentially keep the U.K. in the EU's single market even after an exit from the union.

Banks rose on Thursday after the decision, with shares of Royal Bank of Scotland Group (RBS.LN) (RBS.LN) up 6.7%, Barclays PLC (BCS) (BCS) rising 3.9%, and Lloyds Banking Group PLC (LLOY.LN) (LLOY.LN) 4.1% higher.

Movers: Shares in Wm. Morrison Supermarkets PLC (MRW.LN) climbed 1.2%. The supermarket chain said sales rose in the third quarter ( as its initiative to cut prices had attracted more customers.

On a more downbeat note, Randgold Resources Ltd. (RRS.LN) (RRS.LN) lost 5.9% even as itreported a 55% rise in third-quarter profit ( Citi analysts said the result was weaker than expected.

Resource titan Glencore PLC (GLEN.LN) (GLEN.LN) fell 1.6% after reporting a drop in production in most of the commodities it sells (

Outside the main index in London, Tate & Lyle PLC (TATE.LN) jumped 3.5% after the sugar producer reported an 83% rise in first-half pretax profit (

Spirent Communications PLC (SPT.LN) rose 1.5%. The communications technology company said its Chairman Alex Walker will retire ( and posted a drop in operating profit for the third quarter.

Economic news: The U.K.'sservices purchasing managers index for October rose to 54.5 from 52.6 in September, easily beating analyst forecasts.

(END) Dow Jones Newswires

November 03, 2016 12:06 ET (16:06 GMT)

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