China's leader Xi looms large over North Korean anniversary

As North Korea celebrates a major anniversary this weekend, the presence or absence of Chinese President Xi Jinping could highlight just how much vitality has been restored to ties between Pyongyang and its most powerful backer after a prolonged chill.

A visit by Xi to North Korea for the 70th anniversary of the North's founding on Sunday is expected North Korean leader Kim Jong Un has made three trips to China since March this year and has invited Xi to reciprocate but neither side has said whether Xi will attend.

China could be keen to demonstrate the strong ties it has with Pyongyang to ensure it remains a key player in efforts to dismantle the North's nuclear program. But the celebrations come as President Donald Trump has blamed Beijing for the slow progress of denuclearization.

Below is a look at issues affecting ties between the allies.

Trump suggests that China has been encouraging North Korea to drag its feet with denuclearization to gain leverage against the US in a trade dispute that has seen both sides levelling tariffs on USD 50 billion of each other's products.

On Wednesday, he tweeted that North Korea "is under tremendous pressure from China because of our major trade disputes with the Chinese government," adding: "This is not helpful!" China wasn't having any of it.

Foreign ministry spokeswoman Hua Chunying said Washington should "engage in self-reflection and stop flip-flopping and blaming others."
A visit on such a symbolic occasion would underscore the unique historical ties between the two countries' ruling parties. Mao Zedong sent Chinese troops to aid the North after the Korean War began in 1950, setting up a relationship once described as being "as close as lips and teeth."
"I think Beijing is worried that North Korea will go its own way and work out new relationships with Washington and Seoul and move out of China's orbit."
It "would be a strong signal" if Xi did not go, said Michael Kovrig, senior adviser for Northeast Asia at the International Crisis Group, indicating that "North Korea has a lot to do to get back in China's good graces."