The Vatican's foreign minister, Archbishop Paul Gallagher, voiced hope that Britain would stay in the European Union, suggesting its exit would weaken Europe, Britain's Telegraph reported, citing his interview with ITV that aired on Wednesday.
"I think we would see it as being something that is not going to make a stronger Europe", the archbishop said of Britain's potential exit from the EU.
But he added: "The Holy See respects the ultimate decision of the British people - that's for the British electorate to decide".
The interview came as Wall Street bank Goldman Sachs agreed to donated a "substantial six-figure sum" to Britain Stronger In Europe, a campaign to keep Britain in the European Union, according to a source familiar with the matter.
British Prime Minister David Cameron has promised a referendum by the end of 2017 on whether Britain should stay in the EU.
Prospects of the country leaving the union have raised concerns among sections of its business community and weighed on sterling.