The European Central Bank has reported that its new Frankfurt headquarters is costing 41 percent more to build than expected, Bloomberg reports. The company blames the increase on higher prices for construction materials and “a number of unforeseen challenges.”

The 185-meter tall skyscraper, originally priced at EUR850 million, will now cost as much as EUR1.2 billion (US$1.6 billion), the ECB said in a statement at the topping out ceremony yesterday. Although progress on the project is reportedly six months behind, company says that the completion remains scheduled for 2014.

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