China appears to be keeping its distance as Russia and North Korea move closer to each other with a new defense pact that could tilt the balance of power among the three authoritarian states.

Experts say China's leaders are likely fretting over potential loss of influence over North Korea after North Korean leader Kim Jong Un and Russian President Vladimir Putin signed the deal this week, and how that could increase instability on the Korean Peninsula. But Beijing may be struggling to come up with a response to because of its conflicting goals: keeping peace in the Koreas while countering the U.S. and its Western allies on the global stage.

During daytime, entire districts of Ukraine's capital are disconnected from the power grid to save energy. Traffic lights stop, choking traffic, accompanied by the constant rumble of generators installed outside cafes and shops.

Ukraine, including Kyiv, is struggling to cope with a new wave of rolling blackouts after relentless Russian attacks took out half the country's power generation capacity.

President Joe Biden begins an intense period of private preparations Friday at Camp David for what may be the most consequential presidential debate in decades.

The 81-year-old Democrat's team is aware that he cannot afford an underwhelming performance when he faces Republican rival Donald Trump for 90 minutes on live television Thursday night. Biden's team is expecting aggressive attacks on his physical and mental strength, his record on the economy and immigration and even his family.

South Korea summoned the Russian ambassador to protest the country's new defense pact with North Korea on Friday, as border tensions continued to rise with vague threats and brief, seemingly accidental incursions by North Korean troops.

Earlier Friday, the powerful sister of North Korean leader Kim Jong Un issued a vague threat of retaliation after South Korean activists flew balloons carrying anti-Pyongyang propaganda leaflets across the border, and South Korea's military said it had fired warning shots the previous day to repel North Korean soldiers who briefly crossed the rivals' land border for the third time this month.

Russian President Vladimir Putin signed a series of deals with his Vietnamese counterpart To Lam on Thursday, during a state visit that comes as Moscow is seeking to bolster ties in Asia to offset growing international isolation over its military actions in Ukraine.

The two signed agreements to further cooperation on education, science and technology, oil and gas exploration and health. They also agreed to work on a roadmap for a nuclear science and technology center in Vietnam.

South Korea on Thursday condemned an agreement reached by Russia and North Korea that pledged mutual defense assistance in the event of war and said it will reconsider its policy of limiting its support to Ukraine to non-lethal supplies.

The comments by a senior presidential official came hours after North Korea's state media released the details of the agreement reached between its leader Kim Jong Un and Russian President Vladimir Putin during their summit on Wednesday in Pyongyang.

Both Russian President Vladimir Putin and North Korean leader Kim Jong Un say a new strategic partnership is a breakthrough, but what it means for their relationship is still uncertain.

The pact requires both countries to use all available means to provide immediate military assistance in the event of war, according to North Korean state media. While the agreement, inked Wednesday at a summit in Pyongyang, could represent the countries' strongest deal signed after the Cold War, there are differing opinions on how strong the security commitment is.

Nine people were killed and more than 40 injured when a fire set off explosions at a military ammunition depot in Chad's capital, an official said Wednesday.

Government spokesperson Abderaman Koulamallah said 46 people were being treated for various injuries after the explosions jolted residents from their sleep late Tuesday in the Goudji district of the capital, N'Djamena. The situation has been brought under control, Koulamallah said.

Russian forces have escalated attacks near Toretsk, a frontline town in eastern Ukraine that has remained relatively calm over recent months of fighting, officials and AFP journalists reported Wednesday.

Overwhelmed and outgunned Ukrainian forces have struggled to hold the line in the eastern Donetsk region, which the Kremlin claims is part of Russia.

The European Union's executive arm on Wednesday criticized France for running up excessive debt, a stinging rebuke at the height of an election campaign where President Emmanuel Macron is facing a strong challenge from the extreme right and the left.

The EU Commission recommended to seven nations, including France, that they start a so-called "excessive deficit procedure," the first step in a long process before any member state can be hemmed in and moved to take corrective action.