Extreme weather conditions are hitting coffee production in Vietnam, the world's largest exporter of low-end robusta beans used in instant coffee, an industry official said Friday.

Severe cold and drought saw Vietnam's coffee production in the 2013-2014 crop tumble eight percent on the year before, Do Ha Nam, Vice President of the Vietnam Coffee-Cocoa Association (VICOFA) told AFP.

Higher-quality arabica beans have also been severely affected by continuing low temperatures in the north of the country, he said.

Crops in the main robusta-growing region, in the communist country's Central Highlands, were also hit by a drought last year.

"The cold has severely hit coffee production in recent months in the northwest province of Son La where 1,300 hectares of (arabica) coffee -- more than 10 percent of its total production -- were damaged," Nam said.

"Coffee production for the 2013-14 crop was 1.37 million tons, down eight percent compared to the previous season," he added.

In 2012, Vietnam exported 1.73 million tons of coffee, worth some $3.67 billion and accounting for more than 50 percent of the world's robusta, which is used in instant coffee or other blends.

"The drought especially hit coffee production in the first quarter of 2013, with more than 34,000 hectares affected in the Central Highlands," Nam said.

Vietnam is the world's second-largest coffee producer and is seen as high volume rather than high quality -- its bitter-tasting robusta wins few accolades internationally and is mostly exported as raw beans.

But robusta prices hit a nine-month peak at the start of March and arabica-quality coffee has surged close to 60 percent in value since the start of the year due to a drought in Brazil -- the world's biggest coffee producer and exporter.

A Ho Chi Minh City-based coffee trader for a major international firm remained optimistic that the adverse weather.

"It's dry season -- so you always have dry weather," the trader told AFP, speaking on condition of anonymity.

"It is completely normal. It (a drought) could still happen but we will only know in four or five weeks if the rains don't come," the trader added.