No they do not. Upon arrival, they are given a stamp allowing them to stay in the UK for not more than 6 months.
No need for a visa, as the UK is a participant in the Visa Waiver Program.
Yes
NO, in most cases you do not need a visa to come to the UK for a short visit
No UK citizens do not need a visa to go to Singapore just like Singaporeans do not need a visa to enter UK
no
Yes
No, Serbian citizens doesn't need visa for Schengen countries, but they need visa for UK and Ireland.
No - you still need a visa to enter the UK !
Yes they do.
Yes
No - you can enter the UK for 90 days without a visa for tourist purposes
Did travel document refugee passport genever convetion 1951 NEED VISA FOR gibralter