Britain's top share index was 0.1 percent lower around midsession on Friday with weakness in oils and miner more than offsetting strength in banks, ahead of the release of second-quarter U.S. GDP figures.
By 1028GMT, the FTSE 100 was off 3.18 points at 4,628.43, having closed up 1.9 percent at a 7-month high on Thursday on reassuring company earnings.
"There is no doubt that the headline act will be the U.S. GDP numbers, a number that undoubtedly has the potential to cause a stir on the last day of the trading month," said Jimmy Yates, head of equities at CMC Markets.
"A weaker number here could set the tone for August and show us that we still have a long way to go before we start seeing growth in the world's largest economies."
A Reuters poll of economists showed a median forecast of a 1.5 percent contraction in the U.S. economy in the second-quarter, on a seasonally adjusted annualised basis, compared with a 5.5 percent contraction in the first quarter.
Miners fell back, dragged lower following disappointing results from Anglo American.
Anglo American shed 1.4 percent after posting a sharp fall in first-half profit, having achieved $450 million of its planned $2 billion in cost savings.
BHP Billiton, Eurasian Natural Resources, Antofagasta, Randgold Resources and Rio Tinto shed 0.3-1.2 percent.
Vedanta Resources, however, rose 0.3 percent in spite of saying first-quarter core earnings had more than halved after a sharp decline in metals prices.
Energy stocks were the biggest weight on the index, even though crude remained above $66 a barrel, in response to a generally weak set of earnings results from the majors.
BG Group, BP, Cairn Energy and Royal Dutch Shell fell 1.1-2.7 percent.
BANKS GAIN
Banks were the top performers as investors looked ahead to next week's first-half results.
Barclays and HSBC, which kick off the sector reporting season on Monday, gain 1.3 percent and 1.6 percent, respectively. Royal Bank of Scotland, which reports on Friday, added 0.4 percent.
Lloyds Banking Group, scheduled to release its figures on Wednesday, bucked the trend, falling 0.2 percent.
British Airways led the travel and leisure stocks higher and topped the blue-chip leader board, up 4.8 percent, after the airline said it has cut operation costs by around 6.6 percent since last October as it reported first-quarter operating losses of 94 million pounds.
Banc of America-Merrill Lynch repeated its "buy" rating and said it was "encouraged by comments that traffic has stabilised in Q1 and shows some signs of improvement in Q2 … believe this is the first step in the revenue recovery process."
TUI Travel, Intercontinental Hotels, Thomas Cook, and Carnival rose 1.2 to 2.6 percent.
Tobacco companies were also in favour. Imperial Tobacco and British American Tobacco added 1.4 percent and 1.2 percent, respectively.
Reed Elsevier rallied 2.5 percent higher helped by news Credit Suisse has upgraded its stance on European media to "overweight" from "underweight".
The Anglo-Dutch publisher's shares dropped Thursday on news it had ditched its 2009 earnings per share guidance and its plans to issue new shares to pay down debt.
Blue-chip peers Thomson Reuters and Pearson rose 0.6 percent and 1.5 percent, respectively.
Midcap media firm United Business Media jumped 8 percent as it said it was on track to meet 2009 targets after cutting costs to combat weakness in print and in its trade fairs business, and said forward bookings for major events were up.
British consumer confidence held steady in July as a small deterioration in Britons' expectations of their own finances was offset by a more upbeat view of the economy as a whole, the GfK/NOP consumer confidence index showed.
