Mexico's government announced $23 billion in investments on Tuesday to modernize its refineries while sharply slashing greenhouse gas emissions produced by oil-processing facilities and gasoline.

While world governments held climate talks in Paris, President Enrique Pena Nieto unveiled $3 billion plans to cut sulfur content in gasoline produced at six refineries of state-run firm Pemex, reducing emissions by 90 percent.

The project is to be completed in early 2016.

Another $3 billion will be spent at three refineries and a gas processing plant so that they can produce their own electricity, cutting 3,000 tonnes of greenhouse gases per megawatts generated each year.

The facilities will produce more than 2,300 megawatts of electricity in total, equivalent to the power generated for one million homes, the government said.

This would reduce emissions of carbon dioxide by 1.75 million tonnes per year at the Tula refinery in the central state of Hidalgo alone.

- 'Clean' growth -

"They are green investments, which will take care of the environment and care for the health of Mexicans," Pena Nieto said in a speech in Tula.

"We will have cleaner gasoline, with less sulfur content, which will allow us to reduce greenhouse gas emissions that contaminate the environment and affect the health of Mexicans," he said.

The government will also spend $13 billion to increase Pemex's capacity to process crude oil and another $3.9 billion to reduce the need to import diesel with low sulfur content.

The projects, co-funded by private investments, will generate 63,000 direct jobs.

Pena Nieto said the projects were made possible following a landmark energy reform, which he signed last year and opened the oil and gas sector to private investors for the first time since 1938.

"It is possible for Mexico to continue growing economically and produce greater development while caring for and respecting its environment," the president said.

- Climate talks face deadline -

Mexico was the first developing country this year to submit targets for the United Nations climate conference, pledging that its greenhouse gas emissions will peak in 2026 before falling.

The plan envisions greenhouse gases falling 22 percent and black carbon dropping 51 percent by 2030.

The 195-nation UN talks have been billed as the last chance to avert the worst consequences of global warming: deadly drought, floods, storms and rising seas that will engulf islands and densely populated coastlines.

To reach an elusive deal by a Friday deadline, however, governments must first resolve a handful of decades-old disputes that have blocked the path to a universal climate pact.

Nations remain divided over providing financing to help developing nations cope with global warming, how far to limit planetary overheating, how to share the burden between rich and poor nations, and how to review progress in slashing greenhouse gases.