Venezuela and Russia's top oil producer, Rosneft, have agreed on around $14 billion in investment in the South American OPEC country's oil and gas sector.
Venezuelan President Nicolas Maduro made the announcement late on May 27 after meeting with Rosneft CEO Igor Sechin in Caracas.
He said the funds would allow Venezuela to double its oil production.
Rosneft says that the $14 billion constituted its total investment in current and future projects in Venezuela.
The firm said it had already invested $1.8 billion in Venezuela from 2010 to 2014.
Venezuelan state oil company PDVSA said it had agreed with Rosneft to "create companies together" to boost production of crude oil.
Venezuela, which is one of the biggest oil exporters worldwide, has been hit hard by falling oil prices.