London's top-flight rose 5.4 points to 6878.5, within sight of its all-time closing peak of 6930.2 in December 1999 - and the highest finish since that time - after drifting into negative territory earlier in the day.
It was helped by a strong performance from catering giant Compass after it made a £1 billion pay-out to shareholders.
But elsewhere there was a poor reaction to ITV's latest trading figures while a number of stocks went ex-dividend, meaning new investors are no longer entitled to the latest pay-out.
Sterling also weakened after Bank of England governor Mark Carney dampened expectations that interest rates will rise later this year. The pound finished the session at 1.68 US dollars and 1.22 euros.
The bank increased its forecast for GDP next year from 2.7 per cent to 2.9 per cent, but said there was still plenty of slack in the economy and that inflation should remain at or below its 2 per cent target for the next three years. In Europe, Germany's Dax and France's Cac 40 were flat, while in New York, the Dow Jones Industrial Average was down, as Wall Street benchmark indices slipped from latest all-time highs.
Compass was among the biggest risers in London's top flight, though profit-taking later in the session saw some of its gains pared back. It closed 15.5p up at 996p after it said it would use some of its strong cash flows to return £1bn through a special dividend.
The pay-out came as Compass, which provides catering for schools, workplaces and sporting events, reported a 6 per cent rise in half-year profits to £608 million and hiked its regular dividend by 10 per cent to 8.8p a share.
Significant fallers in the top flight included Sainsbury's, which declined more than 3 per cent or 11.3p to 327.7p, while GlaxoSmithKline dropped 13.5p to 1623.5p after Chinese police accused a senior executive of bribery.
AstraZeneca was up 12p, or 0.5 per cent, to 4654p as hearings about its potential acquisition by Pfizer continued in London.
Pfizer's president of worldwide research and development Mikael Dolsten told MPs a combination of the businesses would create a powerhouse of science.
Broadcaster ITV was the heaviest faller as it reported that its TV audience share dipped to 21.6 per cent in the three months to the end of March, compared with 23.4 per cent a year earlier.
The company's shares fell 6 per cent, off 11.9p at 179.1p.
The biggest FTSE 100 risers were G4S, up 6p at 256.5p, Antofagasta up 16p at 795p, SSE up 27p at 1536p and Experian up 18p at 1083p.
The biggest fallers were ITV, down 11.9p at 179.1p, Sainsbury's down 11.3p at 327.7p, Ashtead down 24p at 835p and Barratt Developments down 9.3p at 377p.