Robusta coffee supply from Vietnam could become tight this month after a jump in March loading, with traders on Tuesday projecting shipments to range widely, from 100,000 tonnes to 190,000 tonnes. Buyers could meet some of their demand in Indonesia, where the harvest is peaking, according to traders at foreign firms in Ho Chi Minh City. Indonesia is the world's second-largest robusta producer after Vietnam.  Tighter supply from Vietnam, which may create pressure to drive up global prices, can partly be balanced by fresh beans in Indonesia. The two combined produce nearly a quarter of the world's coffee output. "Loading this month could be on par or lower than March, as there are not many committed deals left for loading," a trader said. He gave no specific figure in his forecast for April.  Vietnam's March coffee exports almost doubled from the previous month to an estimated 190,000 tonnes, or 3.17 million bags, government data showed. Another trader in the city projected exports this month at 100,000 tonnes to 120,000 tonnes. Domestic prices rose on March 14 to their highest since September 2011, on news that a drought was affecting production in the Central Highlands coffee belt. Several showers fell in the region later in March. Farmers have been holding back beans, expecting more price gains, and that has caused exporters' selling to slow. Most of the beans shipped in the current month were covered by contracts signed a month or two ago.  Every April coffee loading since 2005 has stayed below March shipment, Reuters data shows, as buyers source fresh beans from rival robusta producer Indonesia. Last April, Vietnam shipped 168,000 tonnes, down from 187,000 tonnes in March 2012, government data shows.  With London's robusta futures market reopening later on Tuesday after the long Easter weekend, trading on Vietnam's coffee market was thin as traders waited for clues to prices. Vietnamese robustas, which closely track London prices, stood at 42,500 to 43,500 dong ($2.03-$2.08) per kg on Tuesday in the country's top growing province of Daklak, down from 43,400 to 44,700 dong a week ago. Daklak is about 300 km (190 miles) north-east of Ho Chi Minh City. Liffe robusta coffee closed last Friday at its lowest in more than seven weeks, with the May contract losing $36, or 1.7 percent, to finish at $2,064 a tonne on March 27.  Source: brecorder.com/agriculture-a-allied/183/1170227/