UK's Osborne pledges to 'finish the job' on economy

George Osborne, the U.K.'s Chancellor of the Exchequer, lowered his longer-term forecasts for the country's economic growth Wednesday - and hiked taxes for some multinationals in the U.K.

The Chancellor also announced reforms to the U.K.'s unpopular Stamp Duty Land Tax, a lump sum paid when buying a property, which should make the sum paid cheaper for 98 percent of buyers.

He was criticized by Ed Balls, the opposition Labour Party's Shadow Chancellor, who accused Osborne of recycling previously made announcements and said: "For working people, there is a cost of living crisis."

Companies like Starbucks and Amazon, who have faced negative coverage over their U.K. tax payments, may face a larger tax bill, after he announced a 25 percent tax on profits "artificially shifted" out of the U.K.

Non-domiciled taxpayers who have lived in the country for more than 12 years will now have to pay a £60,000 annual charge.

The Office for Budgetary Responsibility (OBR), an independent body which provides economic projections for the U.K. government, raised its gross domestic product (GDP) forecast for the U.K. to 3 percent growth for 2014, and 2.4 percent in 2015 but cut it for successive years. It now forecasts growth of 2.2 percent in 2016, 2.4 percent in 2017, then 2.3 percent in 2018 and 2019.

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Osborne admitted, as widely expected, that the U.K.'s deficit, the amount the government has to borrow to meet the difference between its tax take and public expenditure remains "too high".

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As expected, he said that Northern Ireland may get the power to set its own corporation tax - but only if current negotiations to get the devolved government up and running again are successful.

He pledged to use money collected by fining banks over the Libor and foreign exchange trading scandals, to pay for improved health services and military charities.

Osborne also spoke of "warning signs" in the developed world, which could limit U.K. exports, and promised a £45 million ($70 million) package to support first-time exporters.

The Autumn Statement, which is announced on Wednesday, is one of the biggest milestones in the U.K.'s economic year.

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With just five months to go before an expected General Election, it should be Osborne's opportunity to lure the electorate to vote for his Conservative Party with a few headline-grabbing measures.

However, his budget is tight at the moment. Wednesday's statement was not a "net giveaway," he conceded.

One of the biggest challenges to the mainstream parties is the rise in support for the anti-European Union U.K. Independence Party (UKIP). Osborne was keen to point out his and Prime Minister's credentials on negotiations with the EU, by claiming the country's EU bill had been reduced.

- By CNBC's Catherine Boyle