UK's FTSE lifted by gains at Next and GKN

* FTSE 100 up 0.6 pct

* GKN (LSE: GKN.L - news) surges on higher profits and dividend

* Next (Other OTC: NXGPF - news) rises after increasing earnings guidance

* BP (LSE: BP.L - news) falls, warns of impact from Russia sanctions

By Sudip Kar-Gupta

LONDON, July 29 (Reuters) - Britain's top equity index edged up on Tuesday, lifted by gains at fashion chain Next and at car and plane parts maker GKN after strong results and outlook comments.

The blue-chip FTSE 100 index rose by 0.6 percent, or 40.50 points, to 6,828.57 points going into the close of the trading day.

GKN surged 8.4 percent after posting higher profits and raising its dividend, while Next rose 2.7 percent after a strong second quarter prompted it to boost its earnings guidance.

"In both cases, good numbers," said Patrick Butler, chief executive at London-based Prime Wealth Group, which had recommended GKN as its tip for August.

"Next has come out with another stunning set of numbers and sales are higher than anticipated," he added.

The FTSE 100 reached a peak of 6,894.88 points in mid-May, which marked its highest level since December 1999, and came close to that level again in early July.

However, the UK stock market has given up some of that ground as the conflict between Kiev's forces and pro-Russian separatists in eastern Ukraine has escalated. After the shooting down of a Malaysian passenger plane over rebel-held territory, U.S. and European leaders agreed on Monday to impose wider sanctions on Russia's financial, defence and energy sectors.

Shares (Frankfurt: DI6.F - news) in oil major BP fell 1.6 percent after BP posted higher profits but warned further Western sanctions on Russia could harm its business there and its relationship with Russian state oil company Rosneft.

Hantec Markets analyst Richard Perry said the uncertain geopolitical outlook was holding back equity markets, even though there were signs that company profits were improving.

"Investors are still fairly cautious about Ukraine and Russia. There's no real drive to push equities higher," he said. (Additional reporting by Francesco Canepa; Editing by Hugh Lawson (Other OTC: LWSOF - news) /Ruth Pitchford)