WikiLeaks received a boost tonight when Switzerland rejected growing international calls to force the site off the internet.

The whistleblowers site, which has been publishing leaked US embassy cables, was forced to switch domain names to WikiLeaks.ch yesterday after the US host of its main website, WikiLeaks.org, pulled the plug following mounting political pressure.

The site's new Swiss registry, Switch, today said there was "no reason" why it should be forced offline, despite demands from France and the US. Switch is a non-profit registry set up by the Swiss government for all 1.5 million Swiss .ch domain names.

The reassurances come just hours after eBay-owned PayPal, the primary donation channel to WikiLeaks, terminated its links with the site, citing "illegal activity". France yesterday added to US calls for all companies and organisations to terminate their relationship with WikiLeaks following the release of 250,000 secret US diplomatic cables.

The Swiss Pirate Party, which registered the WikiLeaks.ch domain name earlier this year on behalf of the site, said Switch had reassured the party that it would not block the site.

An email sent by Denis Simonet, president of the Swiss Pirate Party, to international members of the liberal political group said: "Some minutes ago I got good news: Switch, the registry for .ch domains, told us that there is no reason to block wikileaks.ch."

Laurence Kaye, leader of the UK-based Pirate Party, tonight told the Guardian: "International Pirate Parties now have an integral role in allowing access to WikiLeaks. I wish some of our other politicians had the same guts.

"We support the WikiLeaks project as access to information is the prerequisite for an informed and engaged democracy."

WikiLeaks has been fighting to stay online since releasing a cache of sensitive diplomatic cables to the Guardian and four other international media organisations. Amazon, the world's largest online retailer, dropped the site from its servers on Thursday after being contacted by staff of Joe Lieberman, chairman of the US Senate's homeland security committee.

Everydns.net, the site's US hosting provider, yesterday forced the site offline for the third time in under a week. A series of "distributed denial of attacks" by unknown online activists still bring the site intermittently to its knees.

WikiLeaks founder, Julian Assange, described the decision as "privatisation of state censorship" in the US. Everydns.net said the attacks – which have been going on all week – threatened "the stability of the EveryDNS.net infrastructure, which enables access to almost 500,000 other websites".

• This article was amended on 7 December 2010. The original referred to Switch throughout as a registrar. This has been corrected.