China is seeking to boost ties abroad through trade and investment, particularly in Asia. But as Duncan Bartlett found on a recent visit to Bangladesh, not all Chinese businesspeople are versed in the finer points of diplomacy.
Bangladesh grows mangoes, jackfruit and coconuts
Li Li Lang's verdict on the Bangladeshis is harsh. "They are slow, lazy and dull in the head," she told me as she served up a plate of noodles at her restaurant in Dhaka.
"Too much rice. It makes them sleepy," she complained while directing a severe look at her Bangladeshi waiter.
Li Li was born in Hong Kong but moved to Bangladesh 26 years ago, after marrying her Bengali husband, by whom she has two daughters.
Until recently she was a beautician, and at the age of 52 remains proud of her slim figure and stylish make-up.
She switched to catering after winning praise for her skill with sauces and a wok. Her words may have been rather bitter but her cooking was delicious.
"It takes three Bangladeshis to do the work of one Chinese," she proclaimed, at which point the poor waiter hurriedly jumped to his feet to refill my water glass.
Despite her apparent frustration with her adopted land, Li Li Lang intends to stay. She has even converted to Islam and taken a Bengali name, Shamreen Hassan.
Her Chinese friends, she told me, have largely left the country but their nation's ties with it remain strong.
Take the China-Bangladesh Friendship Bridges which span the capital's rivers. There are six in all, compared to just one UK-Bangladesh Friendship Bridge.
The Chinese bridges have made movement of goods and people easier
I crossed one of the Chinese bridges en route to the northern town of Bogra.
The traffic was chaotic... wobbly rickshaws, three-wheeled taxis and battered buses with passengers on the roof.
But without that bridge, everything would have had to make a long and hazardous detour along the banks of the polluted river below.
Then there is the great hall of the China Bangladesh Friendship Centre in Dhaka's Sher-e-Banglanagar district.
It is used for exhibitions, concerts and political rallies. China built it in 2002 at a cost of about £35m ($56m).
When I visited, it was hosting a convention on agriculture.
Chinese merchants were selling rice to Bangladeshi farmers. They had even brought a cookery book.
Chinese merchants see a huge potential market in Bangladesh
Some nations pump aid money into Bangladesh for schemes involving education or healthcare, but the Chinese like to build big things that people can see and use.
They also like schemes which find favour with local politicians.
At the moment they are sorting out accommodation for members of the Bangladeshi parliament. If an MP needs a second home in Dhaka, away from his constituency, the Chinese can help with the cost.
It seems that expense receipts can be submitted to Beijing with little chance of a scandal in the press.
The political goodwill this nurtures creates an environment in which Chinese companies thrive.
Bangladesh does not manufacture much, except for clothes, so it imports large quantities of goods from China, from motorbikes and generators to soy sauce and socks.
Mohammad Hossain sells Chinese clocks and watches from a small stall in a shopping centre in Gulshan. "My customers really care about price," he told me.
"We could sell Japanese clocks and they would last for 10 years. These Chinese ones only last for two or three years but they are five times cheaper."
Shi Hong Shen, a Chinese businessman who works in telecoms, concurs. "Our Bangladeshi customers always want the lowest price," he told me over an ice cream in the lobby of a smart hotel.
"At the moment we can beat our foreign competitors but it's getting tough. That's why we're focusing now more on quality and service."
There is also a thriving market for imported weapons.
The Bangladeshi military is equipped with Chinese tanks and fighter planes - not that the Chinese want to encourage war or insurgency, they are keen that peace endures and the economy grows.
A few years from now, Bangladesh may be able to develop new industries. It should then be able to extract the vast reserves of natural gas and coal that lie beneath the land, just the sort of commodities that China would value.
Hand of friendship
When commerce is over, it is time to relax. Not that Dhaka is much of a party destination.
Taboos against alcohol and mixing between the sexes limit the social life. But there are places foreigners can enter that Bangladeshis avoid and one of them is the Happy Coffee Sing Along club.
The club does not, in fact, serve coffee but it does have beer and an imported spirit called Shochu.
The staff and all the customers, apart from me, were East Asian.
Mr Kim from Korea took the microphone. He has a tender voice, well suited to songs of seduction.
As he sang, he held a Chinese hostess tightly in his arms. He claimed he wanted to marry her but I suspected their acquaintance would not last.
However, for the Bangladeshis, the Chinese offer of a deep and long-term friendship seems sincere.
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