"This is a huge win for people power," said Greenpeace executive director Russel Norman.
"John Key and the National Party have been dead-set against funding a rail link for years - they've made very disparaging comments about it.
"The fact Key has changed his tune now, shows he's buckled under the massive pressure applied by the public, transport campaign groups and the Auckland Council. It's fantastic news and will make a big difference for all of us living here in Auckland, as well as have a flow-on effect to the rest of the country."
Dr Norman said however bright this result may be, the Prime Minister and the Government could have changed their attitude to the City Rail Link sooner.
The decision to bring funding for the City Rail Link forward comes not as one which should earn praise for Key, but rather for the combined voices of the New Zealand public and representative organisations.
Generation Zero spokesperson Leroy Beckett said the announcement is "a massive step forward for Auckland.
"We are relieved this will finally end uncertainty over funding for the CRL and allow construction to continue on schedule," said Beckett.
It will see the opening of three new stations, enable trains to travel at five minute frequencies on existing rail lines, and open the potential for routes to be constructed to Auckland International Airport and the North Shore in the longer term.
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