* FTSE 100 up 0.5 percent
* Weir, GKN boosted by profit beats
* Barclays drops on $9 bln cash call
Britain's top shares edged higher on Tuesday with upbeat corporate earnings newsflow from the likes of car and plane parts maker GKN and engineer Weir offsetting steep falls in Barclays.
GKN topped the FTSE 100 leader board, up 5.5 percent, and Weir rose 3 percent. Both companies beat first-half profit expectations.
This helped lift the UK benchmark 34.94 points, or 0.5 percent, to 6,595.19.
Barclays, however, fell 4.4 percent fall after it announced plans to raise 5.8 billion pounds ($8.9 billion) from its shareholders to meet capital shortfalls.
The bank also posted adjusted pretax profit of 3.6 billion pounds, just below the average forecast of 3.7 billion pounds from 22 analysts polled by the company.
Trading volume in Barclays was at 85 percent of the 90-day daily average, against the FTSE 100 on just 18 percent.
"It was slightly more than we were expecting to see in terms of the capital raising... Short-term there's probably room for more downside in Barclays, longer-term, I guess people will take the view that with the capital adequacy issues resolved there's room for upside," Matt Basi, trader at CMC Markets, said.
Charles Stanley analyst Bill McNamara reckoned Barclays shares could, in the short-term, slip back towards lows recorded a month ago, at 278 pence.
Sentiment in the sector was dented by the news, with Royal Bank of Scotland and Lloyds off 1.6 percent and 0.5 percent respectively as traders also cited some nervousness ahead of results from the pair later in the week.
"I don't think RBS and Lloyds have got the same issues in terms of immediate capital requirements - I don't think that's what the market is saying... the news out of Barclays today has just given the sector a bit of a shakeout," Basi said.
Weakness from BP, off 2.8 percent, also hampered the FTSE 100's progress, weighing on the index to the tune of 10 points, after the oil major said its spill compensation payouts leapt in the second quarter. The news came as BP's second-quarter results missed expectations.
The earnings season has proved mixed so far. About 36 percent of the STOXX Europe 600 companies have reported second-quarter results, with 55 percent of the firms meeting or beating profit forecasts, according to Thomson Reuters StarMine.
"I think at some point in the next hopefully quarter or so the improving macro outlook (will mean that) analysts can be a little bit more relaxed about upgrading their numbers," Ian Williams, equity strategist at Peel Hunt, said.
"With the market trading at over 12 times forward earnings, without that coming through that looks enough for me for now."