Myanmar's new civilian president, Thein Sein, arrives in China on Thursday for a three-day state visit.
Here are five facts about the complex relationship between China and Myanmar:
*In 1949, Burma, as Myanmar was then known, was one of the first countries to recognise the People's Republic of China. But relations soured in the 1960s following anti-Chinese riots in Rangoon (now called Yangon).
* Following a crackdown on pro-democracy protesters in 1988, the West imposed broad sanctions on Myanmar. China stepped into the void, providing aid and weapons and ramping up trade.
Beijing has continued to provide broad diplomatic support for Myanmar's, though the powerful military remains wary of their enormous northern neighbour.
* Bilateral trade rose more than half last year to $4.4 billion, and China's investment in Myanmar reached $12.3 billion in 2010, according to Chinese figures, with a strong focus on natural resources and energy projects.
* Myanmar gives China access to the Indian Ocean, not only for imports of oil and gas and exports from landlocked southwestern Chinese provinces, but also potentially for military bases or listening posts.
In October, China's state energy group CNPC started building a crude oil port in Myanmar, part of a pipeline project aimed at cutting out the long detour oil cargoes take through the congested and strategically vulnerable Malacca Strait.
* The relationship has had rocky patches of late. In August 2009, refugees flooded across into China following fighting on the Myanmar side of the border between rebels and government troops, angering Beijing. Myanmar has since promised to maintain stability on the border.
In 2007, China's Foreign Ministry published an unflattering account of Myanmar's new purpose-built capital Naypyitaw, expressing surprise that the poor country would consider such an expensive move without first telling its supposed Chinese friends.
(Writing by Ben Blanchard; Editing by Alex Richardson)