The Immigration and Checkpoints Authority (ICA) has responded to Vietnamese demands to explain why a number of women from the country have been turned away at Changi Airport - saying that they did not meet entry requirements.
Vietnamese media reported last week that its Civil Aviation Authority raised the query with Singapore after several women were put on planes back home on occasions dating back to at least last year.
The ICA did not reveal how many women were turned away, but said that although it welcomes visitors of all nationalities, "every visitor's entry into Singapore is neither a right nor automatic, and each entry is considered on its own merits".
A spokesman said visitors can be subjected to additional interviews and checks, adding: "The granting of visit passes to visitors is assessed and determined by the ICA officers at the Singapore checkpoints upon their arrival."
A Vietnam News Agency report quoted Vietnamese officials as saying that the women were turned away because they were found to be using different passports.
One woman reportedly had three showing different identities.
The report also said the women could not explain to officers why they wanted to enter Singapore.
A 26-year-old Vietnamese woman told the Tuoi Tre newspaper that Customs officers ushered her into an "isolation room" with 20 other Vietnamese women.
She was later asked to give details of her itinerary - including where she was staying and how much money she was carrying.
"Not until I gave them my fingerprints was I allowed to enter (Singapore)," she said.
Last year, more than 420,000 Vietnamese nationals visited the country, according to the Singapore Tourism Board - almost a third more than in 2010.
The Vietnam Embassy's second secretary Nguyen Cong Huan told The Straits Times that embassy officials met the ICA last Friday to discuss the issue.
The Straits Times understands the meeting ended cordially, with the ICA clarifying its entry procedures and stressing that these applied to visitors of all nationalities.
It also said that interpreters are available to assist travellers who are unable to communicate in English.