For once, Tawakul Karman's busy entourage of tour organisers and interpreters is nowhere to be seen, as she waits in a quiet corner of a London hotel for our photographer to take her portrait. She may have won an international award for it but peace is a rare thing in the sprightly Arab's life.

Facing another early-morning start after a non-stop day of television interviews and speeches, I wouldn't blame her if she slumped on the banisters of the mezzanine and let out a big yawn.

Instead, she smiles as she notices the unremarkable background music coming from the lobby downstairs, and begins to clap her hands enthusiastically to the beat.

After the many arrests and attempted murders she has faced while leading the revolution in her impoverished homeland of Yemen, clearly Ms Karman has learnt to find energy and joy in even the smallest of life's pleasures – even muzak.

Her supporters were dancing with far more abandon last month after she received the Nobel Peace Prize in Oslo. Alongside two other women, Liberia's Ellen Johnson Sirleaf and Leymah Gbowee, Ms Karman received the medal for her "non-violent struggle for the safety of women and for women's rights to full participation in peace-building work".

Coming from a country whose treatment of its female population has been almost as harsh as that of its neighbour, the arch-oppressor Saudi Arabia, that would have been an achievement in itself. But she was also celebrated for becoming the first Arab woman to be given the honour, and – at 32 – its youngest recipient.

More significantly, it came just a fortnight after Ms Karman's campaign of non-violent demonstrations finally led to the belated resignation of Yemen's widely hated dictator, President Ali Abdullah Saleh, after 33 years of rule.

By the time the Arab Spring began to sweep across the Middle East from Tunisia in December 2010, the journalist-turned-activist had already been holding weekly demonstrations in the Yemeni capital, Sanaa, for almost four years.

"Before the revolution, our demonstrations and sit-ins were about calling for freedom of expression, for releasing detainees, and for human rights and anti-corruption – fair demands," she tells me .

At first her call for change appeared forlorn, and she says many people thought she would just get "bored", come to think it was futile, and stop.

"Nothing happened. Saleh didn't respond to any of our demands. He did the opposite; human rights became worse and worse, corruption became worse and worse. So what was the solution? When the Tunisian people made their revolution, we said yes, this is what we should do. We want to down the regime."

This upgrading of demands was made last February, and Saleh's response was swift. Though her protests were peaceful, government forces responded with gunfire. Hundreds have been killed and thousands injured, and she admits she is "surprised" she is still alive.

"There were many attempts to kill me," she confirms – not least of which when a woman was caught in a crowd with a knife, apparently ready to stab her.

"But I also believe it's one life, and we have to die when we carry an issue, when we struggle. I don't want to die just when I sleep in the street, in my bed. You have to die with your dignity and your freedom."

There had been precious little of that in Yemen before this woman with a beaming smile and an inspirational voice set up her camp in Change Square, Sanaa's equivalent of the now famous Tahrir Square in Cairo.

But freedom is far from secure yet. Protests are continuing, and protesters are still dying.

With Egyptian protesters back in Tahrir, doubts growing over the chances of Libya's National Transitional Council delivering on its promises, demonstrations in Tunisia against Islamist extremism, and the Arab League's efforts to stem killings in Syria faltering, it's a familiar situation across the Middle East.

A year on from the fall of Zine el- Abidine Ben Ali in Tunisia, Yemen is far from alone in finding it hard to turn a revolution into solid democracy.

To ensure the uprisings are not quashed after so much has been achieved, Ms Karman believes the West needs to step up its help.

The centrepiece of her visit to Britain, arranged by the Independent Yemen Group and the Council for Arab-British Understanding last month, was a meeting with the Foreign Secretary, William Hague, to plead for the UK to freeze Saleh's assets. She claims they amount to an astonishing $50bn.

Her argument is simple: those funds belong to Yemen's people, not to Saleh its former President. If the money were handed over, Yemen would not need to go begging for international aid from countries like Britain.

A still more serious concern for her is that Saleh, who arrived in the US yesterday for medical treatment, will use the money to carry on exerting power over Yemen. "He wants to make fire between Sunni and Shia," she says, adamant he will encourage sectarian conflict to bring about civil war so that he can later ride back into power as a supposed saviour.

Saleh's continued influence is hard to ignore. Presidential elections take place next month , but the UN-backed Gulf Co-operation Council agreement which saw him step down – and granted him immunity from prosecution – dictates that only his Vice-President, Abd Rabbuh Mansur al-Hadi, can stand in the presidential elections.

Add in the blunt compromise which means each ministry will be run jointly by the opposition and Saleh-loyalists, and Ms Karman believes the inevitable outcome will be governmental paralysis, a stalemate that will only lead to Yemen tearing itself apart again.

So does she think Mr Hague will take heed of her demands?

"I think that he will do things. I trust people. I gave him the message and I am now waiting for the response."

It is an answer given more in hope than expectation, and so far little has been done to reward that faith. But Mr Hague was left in no doubt about the strength of her feelings.

Dr Galal Maktari, treasurer of the Independent Yemen Group - whose interpretatation skills went largely unused, as Ms Karman had been modest about her level of English – said he saw "moments of pain with Hague, who was really unable to answer some of her questions".

As well as its links to Yemen's bullying neighbour, Saudi Arabia, Britain's policy towards her country has long been complicated by al-Qa'ida's foothold in Yemen, with the UK supporting Saleh's fight against the Islamist militants.

But Ms Karman used her appearance in Westminster to apologise for this, and to assure "this greatest parliament, this greatest people", that the Yemeni people did not welcome terrorists.

Not everyone in Yemen is convinced by her leadership, or her sudden rush of jet-setting diplomacy. Some have claimed she is more interested in promoting herself than helping her country.

But seeing her exhausting dedication to Yemen's cause – about which she will try to convince anyone she meets – there does not seem to be much credence in that argument.

That Yemen's liberation is being led by a woman is remarkable, given the poor standards of women's rights. Ms Karman was heavily abused when she adopted a headscarf instead of the face-obscuring niqab. The country has no law against marital rape, and some girls are married off as young as eight years old.

There was never any chance of Ms Karman's husband ruling over her, however. "My first condition when we decided to marry was he must not deny me from working, and he promised," she says firmly.

And what of the part women have played more widely in the Arab Spring? "Women and men help each other to make this revolution, but women were leading the revolution. And it's a social revolution with a political revolution.

"I encourage all women in every country that she must have her rights and she has to struggle for that. She has to convince people. She can't give up, she must do all she can."

As the Middle Eastern fight for democracy struggles for momentum in its second year, it is a message the whole region should take heed of.

A LIFE IN BRIEF

Born 7 February 1979 in Taiz, Yemen, the daughter of Abdel-Salam Karmana, a lawyer who served as Legal Affairs Minister in President Saleh's government before resigning in opposition to the regime. Her brother, Tariq, is a poet, and her sister, Safa, works for Al Jazeera. She has two daughters and a son with her husband, Muhammad Ismail al-Nihmi, whom she married in 1996.

Education Studied commerce at the University of Science and Technology in Sanaa before taking a Master's degree in political science from Sanaa University.