Gross domestic product shrunk by 1.5% in the first quarter, according to the Office for National Statistics, a better than expected performance that was helped by a surge in activity in March as coronavirus restrictions were eased slightly.

The lifting of the remaining restrictions is expected to unlock a huge surge in growth this summer. But multiple lockdowns and a trade shock caused by Brexit have left UK GDP 8.7% smaller than it was before the pandemic started, meaning the country has a bigger mountain to climb than many other major economies.

Economic output in Italy, another country that was hit hard by the pandemic, is 6.9% lower than before the pandemic. The German and French economies are 4.9% and 4.4% smaller, respectively, while the United States is nearly back to pre-pandemic levels.

The question now is how quickly the UK economy bounces back as its hugely successful vaccination program continues and coronavirus restrictions are relaxed further.

"The burst of growth in March shows that the recovery has been gathering momentum more quickly than we had thought," said Ruth Gregory, senior UK economist at Capital Economics. The economy may return to its February 2020 level even before the end of the year, she added.

Economists at ING said the strength of the recovery depends on how quickly consumers spend savings they've accumulated during the pandemic and whether the government continues to offer tax breaks to business.

Brexit pain

Exports to the European Union continued to recover in March, nearly reaching the level that immediately preceded a historic collapse after Britain completed its exit from the bloc on Jan. 1.

However, there is evidence that new border controls continue to affect trade. Imports from Europe remained sluggish in the first quarter, the ONS said, and were outstripped by non-EU imports for the first time on record.

"There's still a small chunk of firms still struggling with the changes," said James Smith, an economist at ING. "The bottom line is that there will continue to be a slow-burning impact of new trade frictions on the UK economy, even if the immediate teething problems have passed."