UPDATE 1-UK says report on PM Johnson trip to Italy is 'completely untrue'

(Adds spokesman comment)

LONDON, Sept 21 (Reuters) - Britain denied on Monday a newspaper report that Prime Minister Boris Johnson went to Italy last weekend, saying he had not travelled to the country in recent months.

Italian newspaper La Repubblica said Johnson was seen in Perugia from Sept. 11 to 14, citing a statement from the city's airport. It reported that he had travelled there to baptise his young son Wilfred.

"This story is completely untrue," a spokesman for Johnson's Downing Street office said. "The prime minister has not travelled to Italy in recent months. Anyone who publishes these claims is repeating a falsehood."

Earlier, British Transport Secretary Grant Shapps also said the report was wrong.

"As I understand it, it is completely untrue. I double checked this morning and it is an erroneous story." (Reporting by Elizabeth Piper, Guy Faulconbridge and Kate Holton; editing by Sarah Young)