By Kate Clark BBC correspondent in Kabul

A few days after the 11 September attacks, when many Afghans feared America might annihilate their country in revenge for the Taleban's support for Osama Bin Laden, former king Zahir Shah gave one of his rare radio interviews on the BBC Persian Service.

Afghans were not terrorists, he told the nation, and international efforts were under way to resolve the crisis.

"I almost cried," one young man told me, "you can't believe how reassuring it was just to hear his voice."

Overnight, the national currency soared.

As I walked around Kabul, asking people about the return of the frail, 87-year-old former monarch who has lived quietly in exile for 30 years in Rome, the response was overwhelming.

Welcome

"Yes, we'll welcome him, said one man, "when he was our ruler, our king, we had hunger, but we had peace."

"All the ethnic groups in Afghanistan support Zahir Shah - Pashtuns, Tajiks, Uzbeks and Hazaras," said another man.

"All the other leaders and the armed factions couldn't bring peace and stability, but he will."

It is actually quite difficult to find an Afghan who does not want the former king back.

Most people here still call him the king or his majesty or even among some of the Pashtuns, Baba - grandfather.

Some concerns

For the Pashtun tribes of the south and east, the return of the king is particularly powerful.

This is the natural monarchist heartland of Afghanistan - but also the areas which have found themselves most marginalised in the post-Taleban government.

The interim leader, Hamed Karzai, should gain popularity by escorting the former king home.

However, Zahir Shah's popularity and his potency as a symbol makes some very powerful figures fear his return.

Particularly among the fundamentalist parties of the Mujahideen, there are concerns that their opponents may use him as a rallying point.

Fears for his security have delayed his homecoming.

In March, his hosts - the Italian Government - spoke of plots to assassinate him, possibly by al-Qaeda or what they called "Afghan warlords who are against the former king".

Father figure

But politics have also delayed the king's return.

In the end, there was a compromise.

Zahir Shah officially arrives as a private citizen, whose only public role will be to open the loya jirga which will decide the next Afghan government in June.

The more politically ambitious members of his family did not accompany him.

"He's a symbol of unity, a very kind man," said the current Afghan leader, Hamed Karzai, putting the official line, "he's an elderly Afghan, a fatherly figure.

This is his country and he should come."

Compromise

That compromise was evident when I visited Palace Number Eight where the former king will live.

There is a magnificent, six-metre square map of Afghanistan and a smart, carved, wooden four-poster bed.

Other than that, it is a modern, 1970s-built house.

It has been given to him by the state, rather than one of the more magnificent state palaces.

When asked if his accommodation in Kabul sounded good enough, Zahir Shah said he just needed a bedroom, an office and hot water.

He has also said that he never intends to leave Afghanistan again - in other words, he wants to die here.

No-one is quite sure what he will do - just sit in Palace Number Eight drinking tea - or will he drink tea with important delegations?

Changing times

Two years ago, sitting on a quiet news day with a couple of Afghan journalist friends in Kabul, we were discussing what fantasy news stories we would most like to cover.

"That's easy," said one, "the return of the king."

We laughed - it was such an unimaginable event - deep in the civil war, when neither the Taleban or the Northern Alliance favoured Zahir Shah.

Now everything has changed in Afghanistan.

The unimaginable has become possible.

Zahir Shah comes back to Afghanistan as a private citizen, but it is no ordinary homecoming.