The marathon talks stretched well beyond the planned Friday end date, as major polluters resisted calls to ramp up efforts to keep global warming at bay.

Thunberg posted the tweet late Saturday with the comment "travelling on overcrowded trains through Germany. And I'm finally on my way home!''

After two weeks of negotiations in Madrid on tackling global warming, delegates from almost 200 nations passed declarations calling for greater ambition in cutting planet-heating greenhouse gases and in helping poor countries that are suffering the effects of climate change.

Countries remained deadlocked Saturday in talks over combating climate change as U.N. talks dragged on beyond the official deadline with no end in sight.

A pair of protests were held this week at the United Nations Climate Change Conference in Madrid that saw Indigenous activists speak out in opposition to a massive oilsands mine proposed for northern Alberta.

Madrid is hosting two-week, United Nations-sponsored talks aimed at streamlining the rules on global carbon markets.

Jonathan Wilkinson said his first priority in the new Parliament will be figuring out how Canada is going to meet its target for cutting greenhouse gas emissions.

U.S. and Chinese negotiators were hoping to finalize a modest trade agreement in time for the Asia-Pacific Economic Cooperation summit in Santiago.