US Secretary of State Hillary Clinton pledged Saturday that Washington would help Tunisia rebuild its economy and cement democracy, as the cradle of the Arab Spring struggles with reforms.

Clinton met Tunisian President Moncef Marzouki as she continued a tour that will also take her to Algeria and Morocco following a global meeting on Syria in Tunis that ratcheted up pressure on the regime of Bashar al-Assad.

"I come with a very specific and committed statement of support about the political and economic reforms that are occuring here," Clinton said after the talks with Marzouki.

"The political side of the revolution is going quite well," she said.

"I am a very strong champion for Tunisian democracy and what has been accomplished here.... The challenge is how to ensure the economic development of Tunisia matches the political development."

At the start of the talks she also praised Friday's "Friends of Syria" meeting of more than 60 foreign ministers for bringing new pressure to bear on Assad's regime.

"It was quite a successful conference and a great credit to Tunisia, and your words and the prime minister's leadership were a very strong signal," she said.

Washington is keen to support Tunisia's democratic progress and economic success, hoping it will set an example for other countries in the region that have toppled autocratic rulers or are undergoing popular uprisings.

Tunisia, where mass protests ousted strongman Zine El Abidine Ben Ali early last year, launched the Arab Spring and inspired similar movements in Egypt, Libya, Syria and elsewhere.

Authorities in Tunisia, which elected a moderate Islamist government in October, are struggling to deal with unemployment levels of nearly 20 percent and continuing political tensions following the revolution.

The US has vowed to help, committing about $190 million (141 million euros) in total assistance to support the country's transition and setting aside $30 million to guarantee Tunisian government loans or bonds.

Tunisia would also be able to benefit from a new Middle East and North Africa Incentive Fund announced by President Barack Obama this month that has requested nearly $800 million to boost reforms in Arab countries undergoing pro-democracy revolutions.

"I would do my best to provide the support that is needed in the short term," Clinton said, but warned: "I don't want to over-promise. As you know there is a global economic (crisis)."

Friday's meeting on Syria issued a declaration calling for an immediate end to violence and for new sanctions on the country, where monitors say more than 7,600 people have been killed since an uprising against Assad's rule erupted last March.

The group called for Syria's government to "immediately cease all violence" to allow humanitarian access and "committed to take steps to apply and enforce restrictions and sanctions on the regime".

During the meeting Clinton said Assad would pay a "heavy cost" for ignoring the will of the international community.

"The Assad regime has ignored every warning, squandered every opportunity, and broken every agreement," she said. "Faced with determined protestors demanding their rights and their dignity, the regime is creating an appalling humanitarian disaster."