"Of the extra 76 million international arrivals for the first three months, about 47 million were recorded in March, showing that the recovery is gathering pace."
The increase was particularly notable in Europe, which welcomed almost four times as many arrivals as in 2021, an increase of 280 per cent.
Strong growth was also seen in the Americas, where arrivals more than doubled (up 117 per cent) and in the Middle East, up 132 per cent.
"The gradual recovery is expected to continue throughout 2022, as more destinations ease or lift travel restrictions and pent-up demand is unleashed," the agency said, pointing to "a significant increase in flight reservations".
By June 2, 45 destinations (two thirds of which were in Europe) no longer had Covid-related restrictions in place, while in Asia, an increasing number of destinations had begun easing restrictions.
However, the UNWTO retained a prudent outlook for the coming months, given the risks linked to the "challenging economic environment" and Russia's invasion of Ukraine.
"The Russian offensive on Ukraine seems to have had a limited direct impact on overall results so far," it said.
But it was having "major economic repercussions globally" by exacerbating fuel and energy costs "which results in higher transport and accommodation costs for the tourism sector" that could weigh on the sector's recovery, it warned.