China just quietly wrote off a chunk of Cameroon's debt. Why the secrecy?

Cameroon President Paul Biya, left,  with Chinese President Xi Jinping at the Forum on China-Africa Cooperation in September 2018, in Beijing, China.

(CNN)When top Chinese diplomat Yang Jiechi met Cameroon President Paul Biya in the capital Yaounde last month and wrote off a chunk of the African country's debt, the deal very nearly went unnoticed.

China issued no press release, and the Cameroon government did not mention the debt cancellation in its write-up of Yang's visit.
It was only when a Chinese news report later alleged that Beijing had written off 3 trillion Central African CFA francs ($5.2 billion) of Cameroon's debt during Yang's trip that the existence of a deal emerged.
The figure was incorrect. Five billion dollars is close to the amount Cameroon has borrowed from Beijing since 2000, according to the China Africa Research Initiative (CARI), and exceeds the amount the country is believed to still owe.
    But while the news report was wrong, its release did force the Chinese government to speak publicly about what type of deal had been reached.
    Last week, Chinese Foreign Ministry spokesperson Hua Chunying told CNN: "China agreed to waive the interest-free inter-governmental debt that Cameroon had not paid back by the end of 2018."
    That debt was worth $78.4 million. Cameroon's total debt is 5.8 trillion Central African CFA francs ($10 billion), about a third of which is owed to China, according to the International Monetary Fund.
    In short, this was a tiny slice of Cameroon's liability to China.
    So why the initial secrecy?

    African debt backlash

    Debt write-offs for developing nations are usually greeted with great fanfare, such as the IMF and World Bank's Heavily Indebted Poor Countries (HIPC) Initiative, or the Paris Club's landmark debt wipe-out in the early 2000s.
    In China, it's more complicated: African debt has become increasingly controversial at home.