Sweden and 195 UN countries are participating in the negotiations aimed at limiting global warming to 2C. The talks will continue until December 11.
Sweden has been seen by some as a bridge builder in the talks between developed and developing countries and the funds needed to cut carbon emissions.
At a press briefing in the conference centre in Le Bourget, north-east of the French capital, Löfven said that he is proud to lead a government that prioritises the climate.
"Sweden is the biggest donor per capita to the green climate fund," he said and announced that in addition to the 4 billion SEK that Sweden already has given to the fund, another 150 million will go to the UN adaptation fund, and an additional 100 million to the fund for the least developed countries.
Some 150 heads of state have gathered for the first day of the summit. Sweden's king Carl Gustaf was also present.
At the press conference, Löfven noted that what is currently on the table will not go all the way to keeping global warming at 2 degrees, "but if we now negotiate a dynamic agreement it will go far".
There are fears from the group of least developed countries that they will be 'left behind' in the scramble for a new deal, and Sweden's prime minister said the rich must take responsibility.
"The rich world must take the lead and show solidarity. Sweden has been working for this for decades and I am proud to lead a government that gives priority to the climate issue. Sweden will be one of the world's first fossil fuel-free welfare nations," Löfven said.