OPEC has agreed to hold its output ceiling at 30 million barrels of oil per day, Venezuelan Energy Minister Rafael Ramirez said on Friday after a key meeting in Vienna.

"Everybody has agreed to maintain the level of production and we are monitoring the market," Ramirez told reporters, adding that the 12-nation cartel was anxious about the impact of the eurozone debt crisis on demand for energy.

The output decision was in line with market expectations, and comes after ministers stated their satisfaction with current oil price levels.

"We are monitoring the market because the economic situation in the EU is difficult, and when we are meeting next time in December we will have more elements," Ramirez said.

He added: "We have to defend the price, we're going to defend the price."

OPEC ministers had already revealed that they expected to keep oil output levels unchanged, despite demand concerns arising from the weak economic outlook.

Ahead of the meeting, there were indications that OPEC -- which pumps about 35 percent of global oil supplies -- would leave its official oil output ceiling at 30 million bpd, where it has stood since late 2011.

However, actual output exceeds this target level partly owing to high production from kingpin Saudi Arabia, which is the biggest producer in the cartel. It has also risen in recent times owing to recovering production from Iraq and Libya.

The outlook for global economic growth, and demand for oil, has been clouded by the combined impact of Chinese inflationary pressures, the long-running eurozone sovereign debt crisis and uncertainty over policy for the US economy, OPEC says.

The Organization of Petroleum Exporting Countries (OPEC), comprising nations from the Middle East, Africa and Latin America, is mindful that cutting production could raise prices and boost their incomes -- but that this could also hurt the fragile global recovery.