According to a local paper, refined product exports from Venezuela are being reduced because the fuel is needed in the country. This fuel is being used because PDVSA, the state oil company, is unable to produce sufficent gas to satisfy internal demand. Venezuela is already importing natural gas from Colombia, and may need to arrange for natural gas imports from Trinidad. The country has the largest natural gas reserves in South America, but evidently the Chavez administration, as it is prone to do, has put people in charge who can't get the job done - they don't know how to get the gas out of the ground, or Chavez has denied them the funding to do so.
This is quite a contrast to the situation in the United States, where new technology has increased natural gas (methane) supplies so much, the price has dropped, and the US may be exporting more natural gas to Mexico in the future. This happened, of course, because in the US they use a very competitive privately-run gas industry, with hundreds of small companies investing to extract the gas alongside the larger companies.
http://www.el-nacional.com/www/site/p_contenido.php?q=nodo/129729/Economía/Pdvsa-reduce-exportación-de-combustibles