FTSE 100 gave up session gains to close 0.1 percent lower, while the FTSE 250 <.FTMC>, which tends to gain from a stronger pound, rose 0.1 percent.

The blue-chip index shed 2.3 percent this week, its biggest loss in seven weeks. The mid-cap index had its worst week since Dec. 21, dropping 0.6 percent.

Sterling rallied to an 11-week high on growing optimism that Britain will avoid a no-deal Brexit after a newspaper report that Northern Ireland's Democratic Unionist Party has privately decided to back May's Brexit deal next week if it includes a time limit to the Irish backstop.

However, the European Union has consistently said it won't put an end date on the backstop.

Stocks with greater international exposure were among the biggest drags on the main index on accelerating dollar weakness, as AstraZeneca, GSK and British American Tobacco all fell.

Oil majors <.FTNMX0530> erased gains and closed lower despite crude prices rising as turmoil in Venezuela renewed concerns that its exports could be disrupted. [O/R]

Miners <.FTNMX1770> outperformed the main index and climbed to three-week highs as copper and gold rose. Fresnillo surged 6.1 percent on its best day in more than three months and Antofagasta, Glencore and Anglo American all advanced.

Brexit headlines still drove moves although nothing significant has transpired since British Prime Minister Theresa May's Brexit proposed agreement fell through.

"It's not immediately apparent we are any further forward. However, markets still appear to be pricing in the prospect that something will be agreed to avoid a no-deal Brexit," said Michael Hewson, chief market analyst at CMC Markets UK.

Vodafone slid 5 percent, extending Thursday's loss, after it said its key revenue measure deteriorated in the third quarter. The stock is down over 10 percent this year, underperforming the wider index, which is up 1.4 percent.

"South Africa was a hit yesterday. They're still trying to reacquire growth lost from the sale of Verizon Wireless in the States, which was a cash cow. There's no guarantee that acquisitions will work and they are expensive," said Accendo Markets analyst Mike van Dulken.

A.G. Barr, the maker of popular Scottish soft drink Irn-Bru, fell 4.5 percent on the mid-caps index as it flagged prolonged economic uncertainty in Britain and regulatory intervention in the soft drinks industry.

Smallcaps <.FTSC> outperformed with a 0.5 percent gain. Pub chain Fuller, Smith & Turner surged 15.5 percent to its best day on record after agreeing to sell its beer business to a unit of Japan's Asahi.

Shares in AIM-listed Earthport added nearly a third in value after U.S.-based Mastercard topped rival Visa with a 33 pence per share buyout offer. Its shares rose 31.3 percent to their highest in over three years.


Vodafone vs FTSE 100: https://tmsnrt.rs/2S8FxMD

(Reporting by Muvija M and Shashwat Awasthi in Bengaluru; Editing by Toby Chopra)

By Muvija M and Shashwat Awasthi