Selfish governments are putting the continued survival of the European Union at risk, Ireland’s former Taoiseach John Bruton has warned, calling for a return to the cooperative approach that initially defined it.

Bruton, who headed a coalition government from 1994 to 1997, also said greater integration of the euro-zone was not a choice at this point in time, but inevitable to avoid the end of the single currency.

Giving the keynote address at the IPE Conference & Awards in Vienna today, Bruton told delegates they needed to be aware of the risks of climate change and said the issue would impact pension funds’ investment portfolios.

“To protect that investment, pension funds have an obligation to contribute to mitigating climate change,” he said, calling for all funds to measure the environmental impact of investments and how investment activity is helping to mitigate climate risks.

Bruton, who spent five years as the EU ambassador to the US, called on European governments to re-discover the sense of reciprocity – “that you give a little to get a little” – and accept measures that may be detrimental for one country but benefit the Union as a whole.

“That sense of reciprocity is what kept the European Union going for 50 years, and I think it’s being lost, progressively, thanks to the national selfishness, the national egoism that has been generated by the financial crisis,” he said.

Asked his view on the future of the EU, he predicted a two-tier system splitting those that were part of the single currencies, and those that had stayed outside the euro.

“Integration in the euro-zone is not a choice at this stage, unless one is ready to contemplate the collapse of the euro,” Bruton said.

The veteran politician, who was first elected to the Dáil aged 22 and stood down as a TD in 2004, took aim at a number of European governments, notably those of Angela Merkel and David Cameron.

He said the UK Conservative Party’s desire for a single market without a single set of rules was “impossible” and lamented the loss to the EU were Britain to leave the Union.

However, his scorn was reserved for the German government, which he said was least likely to implement structural reforms agreed at European level, despite insisting on them for other countries.

Bruton questioned the German approach to fiscal policy and argued it was nonsensical to leave the next generation “a tidy balance sheet if [the] roads are full of potholes”.

“That’s not a good legacy to leave your grandchildren,” he said.

“Germany is not investing in infrastructure, and if it did, that would benefit Germans, but it’d also […] benefit all over Europe as well.

“And it would preserve that great German achievement, the achievement for which the Germans, I think, deserve more credit than anyone else – that great achievement, the European Union.

“But without reforms, it won’t happen.”

Read all the coverage from the IPE Conference & Awards in Vienna, and watch video interviews with some of its speakers