根据提供的文本生成摘要。



以下是一篇英文新闻报道的内容：

"In a major development, the United States and Russia have agreed to extend the New START nuclear arms reduction treaty for five years. The treaty, which was set to expire on February 5th, limits the number of deployed strategic nuclear weapons for both countries. The decision to extend the treaty was welcomed by arms control advocates, who warn of the dangers of a renewed nuclear arms race between the US and Russia."
The US and Russia have agreed to extend the New START nuclear arms reduction treaty for five years, which limits the number of deployed strategic nuclear weapons for both countries. Arms control advocates welcome the decision, warning about the renewed nuclear arms race between the two nations.