GBP/USD touched highs of 1.4396, up from around 1.4359 ahead of the data.
The Office of National Statistics said gross domestic product rose by 0.6% in the three months to December, up from last month's estimate of 0.5% growth. Economists had expected no change.
The U.K. economy expanded 2.1% on a year-over-year basis, better than the initial estimate of 1.9%. Again, economists had expected an unchanged reading.
The dominant service sector grew by 0.8% the ONS said. Industrial production shrank by 0.4%, with manufacturing expanding just 0.1%.
Another report showed that the U.K. current account deficit widened to £32.7 billion in the fourth quarter, the equivalent to 7% of GDP.
Economists had expected a deficit of £21.1 billion.
The weak current account data highlighted concerns that the upcoming June 23 referendum on Britain's European Union membership could hit investment income, leading the gap to widen.
Sterling was lower against the euro, with EUR/GBP rising 0.19% to 0.7900.
In the euro zone, data on Thursday showed that consumer prices fell 0.1% in March in line with forecasts, after falling 0.2% in February.
The U.S. dollar index, which measures the greenback's strength against a trade-weighted basket of six major currencies, remained close to five-month lows at 94.7.
The greenback remained on the defensive as investors pushed back expectations for a near-term rate hike by the Federal Reserve in the wake of dovish comments by Fed Chair Janet Yellen.
Speaking Tuesday, Yellen said global risks to the U.S. economy, including low oil prices and uncertainty over China underlined the need for a cautious approach to raising U.S. interest rates.