Norway's greenhouse gas emissions rose by 1.5% last year, lifted by the oil and gas sector and industry, making it harder for the government in Oslo to keep promises of deep cuts to limit global warming, official data showed on May 20.

Emissions rose to the equivalent of 53.9 million tonnes of carbon dioxide, up from 53.2 million in 2014, breaking several years of declines, and were above the 51.9 million in the benchmark year of 1990, preliminary Statistics Norway data showed.

In the oil and gas sector, BG Group's new Knarr oil field added most to emissions in 2015.

The rise makes the climate goals of the right-wing government ever tougher to meet. Last year, the government in Oslo said it would cut emissions by at least 40% by 2030 from 1990 levels as part of a U.N. agreement on climate change reached in Paris in December.

Many opposition politicians say the powerful oil and gas sector too often gets priority. Norway has often bought emissions quotas abroad to make up for a lack of progress in cutting domestic emissions.

On May 18, Norway awarded 10 oil licenses to energy companies in the Arctic, opening new acreage for exploration for the first time in two decades.

"Norway has an ambitious climate policy," Environment Minister Vidar Helgesen said in a statement on May 20. "We have to prepare ourselves for more climate measures in future, especially within transport."

Helgesen said emissions would be between 17 million tonnes and 20 million tonnes higher by 2020 without existing measures such as penalties for carbon emissions that Norway was among the first to introduce in the 1990s.

Rising emissions could strain the ruling coalition. The small centrist Liberal Party, which usually supports the minority government to pass legislation in Parliament, said more action was needed on climate change.

"The budget for 2017 that the government is now working on must be the best environmental and climate budget ever," the NTB news agency quoted Liberal leader Trine Skei Grande as saying. "If not, this government has no future."