Finance Minister Bill English has warned that it could take a generation for the global financial crisis to be resolved.
Mr English was speaking at the National Party's annual conference at the SkyCity Convention Centre in Auckland on Saturday.
He told party members that Western governments have been spending more than they earn for years.
For example, putting governments' spending in the context of a household, the US government was spending the equivalent of $36,000 a year when it was earning just $23,000, he said.
"The global economic situation is like a dark cloud on the horizon and it's not going to go away possibly for a generation - certainly for 15 or 20 years."
Mr English said that while New Zealand faces problems it does have the opportunity of taking advantage of strong growth in Australia and the Asia-Pacific region.
He says household debt is also coming down and he signalled action would be taken to stop banks from lending more heavily again.
"We don't want to let the banks get carried away with large growth in lending. We have the tools to limit their ability to do that and those tools are in place and can be used."
Mr English said the Government is focusing on policies which make it easier for businesses to grow.
Protest outside conference
A small group of protesters was outside the SkyCity conference venue in central Auckland on Saturday.
In addition, about 150 protestors from the education sector marched up Queen St on Saturday afternoon to show their discontent at the Government's education policy.
The group was hoping to converge on the convention centre but the police have said they will not be allowed to reach the venue.
In his opening address, Mr Key said one of the great things about New Zealand's democracy is the right to protest and another is the right of the democratically elected Government to get on with the job it has won a mandate for.
"So, let me assure you and everyone else watching, that that's exactly what we'll be doing."
Earlier, Mr Key said the party was in good heart and united, despite the Government facing a number of difficult issues this year.
He said things always get more difficult in the second term of office and he is confident the Government has the support of the party.