A trader monitors the screen on a trading floor in London.

London - Britain's top equity index was on track to record its biggest weekly gain in six months as it rose on Friday, helped by a rally in heavyweight miner BHP Billiton.

The FTSE 100 was up 32.09 points, or 0.5 percent, at 6,717.35 points by 09:16 SA time, setting it on course for a 2.3 percent rise on the week, the largest since February.

The week was marked by a dovish message by the Bank of England, which led investors to push back expectations for an interest rate increase, and a general rebound in global equity markets after two weeks of steep declines.

Traders had welcomed conciliatory comments from Russian President Vladimir Putin on Thursday, but tensions between Ukraine and Russia remained high, keeping investors cautious about the market's near-term prospect.

Dozens of heavy Russian military vehicles massed on Friday near the border with Ukraine, where a huge Russian convoy with humanitarian aid came to a halt as Moscow and Kiev struggled to agree on border crossing procedures.

“Short-term I'd probably be 'short' the FTSE because the issues in the Ukraine could influence this market and I think they are going to keep it on a knife's edge,” Mark Priest, senior trader at ETX Capital, said.

The FTSE was still down 2 percent since late July, dragged down by geopolitical tensions from Ukraine to the Middle East, as well as concerns about a tightening of the US monetary policy.

Helping support the FTSE on Friday was global miner BHP Billiton, which added 5.4 points to the index after it declared its preference for a demerger of its unwanted aluminium, manganese and nickel assets. Its shares rose 3 percent.

The demerger would set the stage for the formation of a separate company that one report said could be worth $14 billion.

The second release of Britain's second-quarter GDP data, due at 10:30 SA time, is expected to show the UK economy grew by 0.8 percent quarter-on-quarter in the three months to the end of June.

Earlier this week, the Bank of England slashed its wage growth forecasts, leading money market investor to push back expectations for a UK interest rate rise until the first quarter of next year at the earliest. - Reuters