Gilad Shalit's father has begun a high-profile, 11-day march from his Galilee home to Jerusalem, prompting analysts to predict that Israel will soon resume negotiations with Hamas over the kidnapped soldier.

When Noam Shalit set out from the village of Mitzpe Hila on Sunday, two days after the fourth anniversary of his son's capture by Palestinian militants, it marked a sea-change in his campaign. He has always steered clear of large-scale, direct action and resolved to work with the government, with the exception of the final days of the Ehud Olmert administration when he was hoping for Mr Olmert to close a deal.

But the march has mobilised thousands along the route, all protesting the failure to free Gilad, and now members of the Shalit family are blasting the government.

The soldier's grandfather, Zvi Shalit, called on Monday for Prime Minister Binyamin Netanyahu to give "an explicit declaration that Gilad will be freed, and therefore cut short this long exhausting march".

Hamas is demanding that Israel frees 1,000 prisoners in return for Shalit. In December the two sides were reportedly close to agreement, but talks then stalled.

Shimshon Liebman, head of the Shalit campaign, said that it changed its approach "because we trusted the government for almost four years and saw that this won't bring their son back home".

The Shalits appear to have broad public support. In a survey commissioned by the newspaper Yediot Aharonot, some 72 per cent of respondents were for a prisoner exchange and just 21 per cent were against.

The poll also indicated that the public supports the march, with 83 per cent of respondents saying it is the correct thing for the family to do. There is a widespread feeling that the government should be doing more, with two thirds of respondents claiming that it is not doing "everything it can".

Yaacov Shamir, a communications professor at Hebrew University who has conducted research on the campaign, said that after such a high-profile march. He added: "Netanyahu will feel that he owes a response to the Israeli public."

The march will have "a great deal of impact and will probably push the Israeli government to restart negotiations", he predicted.

In the media there have been many items supporting the Shalits, but there have also been cautionary voices.

Channel 1 ran a report claiming that of the 400 prisoners released in a 2004 swap, half had returned to terrorist activity and one carried out an attack in Beersheba shortly after he was released, in which 16 Israelis were killed.

Some are scathing of the Shalits' campaign. Meir Indor, head of Al Magor, an NGO that represents the families of terror victims, claims that as they are calling for compliance with Hamas's demands, the family has become the "long arm of Hamas in Israel".

Mr Liebman said that he is aware of his campaign being manipulated by Hamas, one of whose leaders, Khaled Mashaal, declared on Monday that the price will rise for Shalit and that Hamas hopes to kidnap more soldiers.

"We know that what we are doing gives a lot of power to Hamas," said Mr Liebman. "Mashaal and the terrorists are trying to use every word we say. But it seems that if we don't take this course of action, nothing will move."