Green Party leader Eamon Ryan has described as shocking the latest upsurge in gang-related killings and said if gardaí need extra resources to keep the peace, they should be provided.

Speaking on RTÉ's Six One News, he said the real key, however, is public support and assistance in rallying behind gardaí.

In relation to the non-jury Special Criminal Court, he said: "In principle, you want juries in all court cases, but there are instances where you have gangland operators who would undermine any jury system where you do have to have the ability to say - only in those cases you need a special court so that you can prosecute people fairly and properly."

Mr Ryan said the Green Party in government made no easy choices, but the party had to respond to the [economic] crisis and not walk away.

He said, if elected, the Green party would retain a water conservation charge because investment in water is needed, but the party would "do it in a very different way".

He said the party would be in favour of a referendum, ensuring that the public's ownership of the public's water supply is held secure, adding that the party does not want a commercial semi-state company.

He said a lot of the money needed for water would have to be raised through general taxation.

On climate change, he said a national plan is needed to set the country in "a greener direction", looking at enterprises and infrastructure.

Mr Ryan also said a national plan is also needed to manage Irish land.