Speculation about OPEC's response to a 30% drop in global oil prices since late-June intensified after calls from Venezuela to increase cooperation within the cartel as well as with non-members, including top producer Russia.

A special global meeting is being planned "very soon", Venezuelan President Nicolas Maduro said on Monday.

"We have coordinated for a special meeting very soon of OPEC and non-OPEC countries to take decisions in defence of oil and the prices of oil and the global oil market," Maduro said in a speech on live TV, without giving any more details.

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