Sterling dipped and the FTSE 100 eked out gains, as investors digested earnings from International Consolidated Airlines Group (IAG) and considered a ruling from one of the first Brexit court cases.

The FTSE 100 rose 0.1% or 9.7 points to reach 6996.3, led higher by IAG shares which rose 24.5p to 438p despite warnings that ticket prices may rise after profits were hit by a slump in sterling and air traffic control strikes.

Investors appeared to welcome a 10% rise in dividends and news that IAG clinched a new pensions agreement with BA earlier this week, putting a cap on any extra contributions the carrier could be forced to make.

Sterling was trading relatively flat against the US dollar at 1.215, and down by 0.4% versus the euro at 1.111.

It marked a slight recovery for the currency, which dipped on news that Northern Ireland's High Court dismissed the UK's first legal challenge to Brexit.

A judge ruled that there was nothing in the 1998 Good Friday peace agreement to prevent the Government from triggering exit negotiations with the EU, despite claims from a cross-party group of politicians the Stormont Assembly should have a say on whether to begin talks.

Across Europe, the French Cac 40 closed higher by 0.3% while the German Dax finished lower by 0.2%.

In oil markets, Brent crude prices fell by 0.7% to 49.93 US dollars per barrel as doubts grew over an oil producer deal.

Opec and non-Opec oil producers, including Russia, began two days of negotiations on Friday that could result in a supply freeze deal meant to support floundering crude prices. However, it is unclear whether countries like Iraq would be granted reported requests for exemptions from the deal.

In UK stocks, Royal Bank of Scotland (RBS) shares closed lower by 2.4p to 194p, after the bank swung to a £469 million loss in the third quarter and confirmed that it will miss a 2017 deadline to sell off its Williams & Glyn branch network.

RBS, which is still 73% owned by the Government, was stung by £425 million in conduct and litigation charges, largely linked to the sale of mortgage-backed securities in the US, and £469 million in restructuring costs.

Away from the top tier index, Halfords shares rose 6.8p to 345.8p after the company announced it would take advantage of the electric car boom by introducing specially trained electric and hybrid car mechanics to each of its 300 autocentres.

The biggest risers on the FTSE 100 were International Consolidated Airlines Group (IAG) up 24.5p at 438p, Sainsbury up 10p at 254p, Barratt Developments up 17.8p at 456.7p, and Next up 168p at 4,974p.

The biggest losers on the FTSE 100 were Shire down 168.5p at 4,781.5p, Intu Properties down 5.4p at 276p, Prudential down 26.5p at 1,369p, and Hikma Pharmaceuticals down 32p at 1780p.