The European Union extended tariffs on Chinese and Vietnamese shoes for 15 months in a bid to help southern EU producers compete against lower-cost footwear imported by companies such as Nike Inc., Puma AG and Adidas AG. The extension of the duties as high as 16.5 percent on leather shoes is a compromise because a U.K.-led group of northern European nations opposed re-imposing the levies for the usual five-year period. The duties aim to counter below-cost -- or “dumped” -- imports from China and Vietnam. The EU goal is to curb competition for 8,000 European leather-footwear manufacturers, mainly small businesses in southern Europe. Four-fifths of the EU’s leather shoes come from Italy, Portugal and Spain, where producers are in the process of becoming more competitive, according to the bloc. European shoe manufacturers are “adapting their business models to the challenges of the globalized market,” the 27- nation EU said in a decision today in Brussels. “Should measures be maintained, they will serve as an additional safety net and allow for more time to continue this process.” The trade protection helped reduce Chinese and Vietnamese exporters’ combined share of the EU shoe market to 28.7 percent in the 12 months through June 2008 from 35.5 percent in 2005, according to the bloc. Over the period, China’s share fell to 18.5 percent from 22.9 percent and Vietnam’s share dropped to 10.2 percent from 12.6 percent, said the EU.