European leaders at the UN climate conference have pledged continued action to tackle climate change. The vow comes despite their growing use of coal amid the energy crisis, resulting from Russia's invasion of Ukraine.

Global leaders entered the second day of their summit-level meeting at COP27 in Sharm el-Sheikh, eastern Egypt, on Tuesday.

German Chancellor Olaf Scholz acknowledged that his country was reactivating coal-fired power plants for a short time to compensate for a drop in natural gas supplies from Russia. But he stressed that Germany remained committed to phasing out coal.

British Prime Minister Rishi Sunak said, "Putin's abhorrent war in Ukraine and rising energy prices across the world are not a reason to go slow on climate change. They are a reason to act faster."

Sunak also underscored the importance of boosting investment in renewable energy sources.

The world is watching closely to see how countries plan to bolster their efforts to mitigate greenhouse gas emissions by 2030.

The question is whether the European leaders' cases are convincing enough for developing nations, which are urging developed countries to do more in their reduction programs.