Some support an Israeli invasion of Gaza, others want a prisoner swap, but relatives of dozens seized by Hamas said Sunday they were united in demanding Israel's government end their nightmare.

More than three weeks after shock cross-border attacks on Israeli kibbutz communities, towns and army bases near the Gaza border, the fearful families feel they are only just starting to be taken seriously by the authorities.

"It was not enough but it was a nice start," said Jackie Levy, an Israeli television presenter among about 80 hostage relatives who met with President Isaac Herzog on Sunday.

"At last we are on the table. They have us and our interests on top of the agenda."

On Saturday, Israeli Prime Minister Benjamin Netanyahu held a hastily arranged encounter with other relatives who had threatened to organise protests over the lack of contact from the government.

"The president told us very clearly that bringing out our beloved ones is a top aim of Israel now," said Levy, whose wife is waiting for news of five relatives seized at the Nir Oz kibbutz.

"It makes us feel a little bit better after three long weeks with no call," he added.

"There is a tremendous intelligence and operational effort that history has not seen before, all to obtain any possible information," government hostage envoy Gal Hirsch told the meeting, according to the families.

The families said they had secured a commitment to give more frequent updates about efforts to release the captives, who are believed detained in Hamas underground tunnels.

The Israeli military says it has confirmed that at least 239 hostages, including toddlers and elderly people, were seized on October 7.

The Palestinian group's military wing has said that "about 50" of them had died in Israeli strikes.

- 'One big family' -

Israel says that 1,400 people, mostly civilians, were killed in the Hamas attacks that set off the war.

Gaza's Hamas-run health ministry says more than 8,000 people, including thousands of women and children, have been killed in Israeli air and ground strikes since.

The relatives of the hostages said no open calls for a ceasefire or prisoner release were made at the meeting.

But there are debates on the many WhatsApp groups and family meetings, they said.  

"There are different opinions but we are all one big family, we have a common goal," said Maya Shoshany, whose father David Moshe was killed at Nir Oz.

Her mother Adina was kidnapped, and later shown in a Hamas social media image riding between two Hamas gunmen on a motorbike.

Levy said the Israeli army was "strong enough to overcome the contradiction between the military aims and the humanitarian".

Hamas leaders have demanded the release of some 5,200 Palestinian prisoners in Israeli jails, in exchange for the October 7 hostages.

But Israel's Defence Minister Yoav Gallant told some relatives Sunday that Hamas was playing "psychological games" and that the military campaign would help end the captive crisis.

- 'War goes on' -

Some families back a prisoner exchange.

When asked about the Hamas demands, Ifat Kalderon, whose cousin is a hostage, said at another meeting on Saturday: "Take them, we don't need them (the Palestinian prisoners) here."

Some relatives said they would want to see more pressure from the Israeli government and other nations.

Ronen Karavany, a lawyer whose nieces Sharon Kunyo and Danielle Aloni were seized, said Israel should seek help from the United States and Qatar, which helped mediate freedom for the four hostages to return so far.

They also plan their own campaign to make sure that the captives are not forgotten.

"We want to give each of them a name and a face, a story and a family, and a context," said Levy.

Shai Wenkert, whose 22-year-old son was seized at a music festival where about 260 people were killed, said: "The war will not end until all the families come back. Until then the war goes on."

Talking of his own ordeal, Wenkert said: "We have to be strong. He is a strong guy and we are waiting for him at home."

tw/jd/ami/leg