The Federal Government has announced an $80 million boost to polio funding as the world's richest man, Bill Gates, keeps up the pressure on Australia to stay committed to foreign aid.

Speaking at the National Press Club, Mr Gates acknowledged that massive writedowns in tax revenue had made for a tough budget.

But the Microsoft founder said progress towards an aid target of 0.5 per cent of gross national income was important.

"Countries like Australia ... have continued to be generous to the poor even as global economic conditions have been very tough," he said.

"If we look at this as a percentage of gross national income, which is the standard measure how this is done, you can see Australia measures up fairly well. Not at the very highest, but definitely making progress."

Australia's foreign aid level is around 0.37 per cent of gross national income and the Government has delayed reaching its 0.5 per cent target until at least 2017-18.

Government announces $80m boost to polio fight

Shortly before addressing the National Press Club, where he lobbied for an increase to Australia's $5 billion overseas aid budget.

Ms Gillard and Foreign Minister Bob Carr later issued a statement announcing $80 million over four years to help eradicate polio.

The Bill and Melinda Gates Foundation is contributing $US1.8 billion to help eradicate polio.

The Government's announcement brings its total funding for the Global Polio Eradication Initiative to $130 million.

Mr Gates says his foundation already has strong partnerships with Australian groups in the health and agriculture sector.

"There's opportunities, of course, to do more, whether it's more Australian research in health or in agriculture, more to delivery both in the region and to the poorest countries worldwide," he said.

He says aid has more than just humanitarian benefits.

"If you think about stability in the world, aid will be critical there," he said.

"For Australia, 18 of your closest neighbours are developing countries and so in some ways the imminent neighbourhood where some of these tough challenges are still very big are close at hand.

"Whether it's regional issues or economic opportunity, the solutions of these problems will make improvements that will benefit Australians and the entire world."

Gates explains switch to philanthropy

Mr Gates, who is worth about $67 billion, told the Press Club he was often asked why he left his career at Microsoft to focus on philanthropy.

"I loved my work at Microsoft. It was thrilling. At age 13 I got exposed to computers, saw that they were magical, heard that they were magical," he said.

"I devoted myself to creating a company that would participate in building the software that would bring that capability to life, that would give us all a tool to communicate and create in new and different ways, and that digital revolution is literally just at the beginning.

"I saw that technology doesn't naturally get to those most in need and, in fact, that their most basic needs are not related to IT or the digital revolution in any way.

"Their needs are based on wanting their child to live, to have nutrition to grow up to achieve their potential."

He says he has now committed his life and resources to philanthropy.

"It's very gratifying," he said.