LONDON (AFP) - Asian and European stock markets charged upwards on Friday, aided by an overnight rally on Wall Street, as optimism in the global economy returned ahead of the weekend, dealers said. Comments from the head of the European Central Bank gave dealers the impetus to seek more risky assets, although leading economists warned there were still lingering concerns over the continents debt. The appetite for risk has improved dramatically over the past few sessions of trade, with a number of positive developments in the global macro economy helping to bolster the improved sentiment, said analyst Joel Kruger at currency trading website Daily FX. The welcome progression of solid Chinese export data, stronger Australian unemployment, rate hikes from New Zealand and Brazil, successful debt sales in Spain, Italy and Ireland, and a German court rejection on attempts to block EU/IMF aid, are all seen as the primary drivers, he added. It will now be interesting to see if the markets can build on this momentum in the final trading day of the week. Londons stock market climbed 0.82 percent in midday trade, boosted also by a strong rebound in shares of troubled British energy group BP. Stocks in Frankfurt gained 0.15 percent and Paris rose 0.97 percent. Madrid soared by 4.34 percent in value, with Spanish banking stocks amongst the biggest gainers thanks to the quickening pace of consolidation of Spains unlisted regional savings banks. A strong finish to trading on Wall Street on Thursday has given a welcome boost to shares in London, said Anthony Grech, head of research at financial spread-betting company IG Index. Troubled oil company BP is still very much at the front of traders minds and so far today it has managed to reverse almost all of Thursdays losses. BPs share price soared 8.36 percent to 396.09 pence on bargain-hunting after recent heavy losses, despite negative news over the Gulf of Mexico oil spill disaster, dealers said. The stock had closed down 6.65 percent on Thursday, after hitting an intra-day low of 330 pence, as investors fretted about the financial impact of the oil spill and the possible loss of the groups shareholder dividend. Data suggesting the oils flow could be upwards of 40,000 barrels a day more than double the previous forecast rounded off a miserable day for BP on Thursday. The latest news that there may have been twice the amount of oil lost before the well was capped has had little effect on sentiment, added Grech. Meanwhile in Asia on Friday, Hong Kong shares added 1.22 percent, Sydney gained 1.58 percent and Tokyo leapt 1.70 percent. Wall Street gave a strong lead, with the Dow surging 2.76 percent Thursday on upbeat data out of Asia that showed Japans economy growing quicker than initially thought, Chinese exports soaring and Australian unemployment falling. Markets were also given a lift after ECB chief Jean-Claude Trichet said the euro is credible, keeps its value and is a major asset for domestic and exterior investors, after eurozone borrowing costs were kept at 1.0pc. In foreign exchange trade on Friday, the euro eased to 1.2119 dollars from 1.2122 dollars late in New York on Thursday. The dollar firmed to 91.61 yen from 91.32.