A popular Moroccan proverb goes: "A man without friends is like a garden without flowers." It was told to me in the first week I arrived to live in Casablanca, almost three years ago, by a plumber who had turned up to clean out the drains. He seemed distraught that I could have moved to a foreign land where I knew no one at all. I told him that it felt liberating.

"I don't have to avoid people any more," I said, beaming. The plumber wiped a rag over the crown of his bald head.

"But how will you live if you don't have friends?" he asked.

Looking back to that first week, I now understand what he meant. For us in the west, friends are sometimes little more than people we go to the pub with so that we aren't there alone, but in Morocco, friendship is quite a different thing. It is a support structure par excellence, a system by which the old values of chivalry and honour are passed on. But more than that, it is some-thing that is actively nurtured and raised, like a seedling in a garden.

My story is not unusual. I had been lured to Morocco from London to escape the damp grey sky and the exorbitant costs of living in Britain. The house we found was quite grand, a thousand times larger than our London flat. It was located smack in the middle of a thriving shanty town.

Your learning curve is a steep one when you move to a new country. Over the first year, we renovated the house, exorcised the wayward djinns who supposedly inhabited it, and battled against the waves of conmen who beat a path to our door. At times, I would find myself wondering if I would ever find anyone in Casablanca who I could trust, a real friend. Then, one spring morning, I met Abdelmalik.

I was having my hair cut at a run-down barber's shop near to my house when a tall, suave man burst in and sat on the chair beside mine. He asked for a shave. A pair of dark glasses was worn like a tiara across his slicked-back hair. He smiled a great deal. I supposed he was in his late thirties. While the barber sharpened the cut-throat razor on a leather strop, the man made conversation.

He asked me if I missed England. "How do you know I've come from England?" I asked.

"Because you look too pale to be Moroccan and too content to be French."

The man's cheeks were shaved and anointed with a home-brewed cologne. He pressed a coin into the barber's hand. "I will wait for you at the café opposite," he said.

I was still unfamiliar with Moroccan society, and wondered if I should accept the invitation. But, unable to resist, I crossed the street and found the man, Abdelmalik Leghmati, sipping a café noir. We sketched out the broad details of our lives - wives, children, work - and we exchanged telephone numbers. He expressed his great love for Arab horses and his lifelong dream of owning one. It was an interest we both shared. We chatted about horses and life for an hour or more. Then Abdelmalik glanced at his watch.

"We will be friends," he said firmly, as he left.

From then on the suave, clean-shaven Moroccan swept into my life. He saw it as his duty to solve every one of my abundant problems and to help me settle in. First, he taught me local etiquette: how to make myself be regarded as a local, how to receive and entertain a Moroccan guest, and how to prepare the sweet mint tea that everyone drinks constantly.

From the outset, Abdelmalik stressed again and again that I could ask anything of him. It was his duty, as my friend, to be there for me. I found it strange at first that someone would make such a point about friendship, rather than just letting it develop. We'd meet at least every other day on the terrace of Café Lugano, near Casablanca's coastal road, where we always sat at the same table. I commented that the same people were usually sitting at the other tables as well.

"Of course, that's how it is," said Abdelmalik. "You see, they are friends."

In Morocco there is no occupation more honourable for a man than to be seen with his pals, sitting at a café, drinking sweet mint tea. In the west, we might frown on spending so much leisure time in such a way. For Moroccans, however, time spent working on a friendship in public is extremely important.

When I told an expatriate acquaintance about Abdelmalik, he waved his arms in caution.

"Beware!" he shouted. "Before you know it, this man will be demanding you to repay his kindness. What happens if he gets into a family feud?" The expatriate paused. "You could even find yourself at war," he said. "And all because you are his friend."

After we had known each other for a month, Abdelmalik invited me to his apartment. It was small, cosy and dominated by a low coffee table. On the table were laid at least ten plates, each one laden with sticky cakes, biscuits and buns. I asked how many other people had been invited.

"Just you," replied my host, confused.

"But I can't eat this much," I said.

Abdelmalik grinned like a Cheshire cat. "You must try to eat it all," he said.

A few days later, he called me and announced he had a surprise. An hour later, I found myself in the steam room of a hammam, a Turkish-style bath. For Moroccans, going to the hammam is a weekly ceremony. Abdelmalik taught me how to apply savon noir, and the ritual of gommage - scrubbing myself down until my body was raw. In the scalding fog of the steam room, he presented me with an expensive wash-case packed with the items I would need. When I choked out my thanks, embarrassed at the costly gift, he whispered: "No price is too great for a friend."

Months passed, and I found myself waiting for Abdelmalik's ulterior motive. I felt sure he would eventually ask me for something, some kind of payment for our friendship. Then, one morning, after many coffee meetings, he leaned over the table at Café Lugano and said:

"I have a favour to ask you."

I felt my stomach knot with selfishness.

"Anything," I mumbled, bravely.

Abdelmalik edged closer and smiled very gently. "Would you allow me to buy you an Arab horse?" he said.

Tahir Shah is the author of "The Caliph's House: a year in Casablanca" (Doubleday, £15)