BANGKOK, May 3 -- Across Bangkok, aromas of garlic, chilli and grilled meat drift from roadside stalls and carts, but tighter controls on vendors threaten livelihoods and the street food culture that defines the Thai capital.

Convenient, full of flavour and popular among locals and tourists alike, Bangkok's street food is one of the city's signatures - where sizzling woks and smoky charcoal grills turn boulevards and sidewalks into open-air kitchens from morning until late at night.

But many street sellers in the foodie paradise face an uncertain future as the Bangkok government in recent years has moved to clear footpaths, improve order and relocate vendors from curbsides in packed commercial districts to designated market stalls.

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