The new British Library UK web archive may store 220TB (terabytes) of data annually from 2011, it said last week.
The project aims to store all UK free-access websites. It has been developed with the National Archives, the national libraries of Scotland and Wales, Jisc, the Wellcome Library and partners, including IBM.
Examples of the type of material it aims to store are the websites of the 2012 Olympic and Paralympic Games and the 2005 general election, the first in which candidates used the web as a campaigning tool.
Work is also under way to store the websites of MPs who will retire at the next general election, creating a record of their time as Members of Parliament.
The British Library said the UK's web domain has some 8 million sites with an average life expectancy of between 44 and 75 days. Material that is freely available on the web is still subject to copyright and cannot be archived without permission. But the library hopes Parliament will change the law, following a Department for Culture, Media and Sport consultation which closed on March 1.