US President Barack Obama has said there are "signs of economic progress" but underlined that times remain tough.

美国总统奥巴马表示已有“经济复苏的迹象”但是仍强调局势依然很严峻。

Separately Federal Reserve head Ben Bernanke talked of "tentative（实验性质的，暂时的） signs" that the contraction¹（收缩） rate was calming.

But both men, speaking independently to students, said recovery would take time and more job losses would follow.

Their statements came after earlier data showed disappointing retail²（零售） sales for March after two months of rises, a signal that consumers were cautious（小心的，谨慎的）.

The fall in retail sales was unexpected, suggesting the worst might not yet be over.

Mr Obama, who was speaking at Georgetown University, pointed³ to the US government's housing plan as a factor in boosting the economy, as the number of people refinancing（重新募集资金） their loans increased.

He added that support for the auto⁴ and student loan markets had also contributed to an easing of credit conditions along with progress at this month's G20 meeting.

But he warned that more work needed to be done and that "credit was not flowing nearly as easily as it should".

He also said 2009 would be a hard year for the US economy, when there would be more job losses, more repossessions（恢复） and "more pain before it ends".

Financial markets

And Mr Bernanke, who was talking to students at Moorehouse University in Atlanta, said: "A levelling out of economic activity is the first step towards recovery".

But he added: "We will not have a sustainable（养得起的，可以承受的） recovery without a stabilisation of our financial system and credit markets."

The central bank has reduced interest rates to near zero in a move to boost the economy and encourage spending.

But problems in the credit markets have continued to make borrowing for individual and firms hard and expensive.

Mr Obama was greeted with applause when he said the first task was to ensure such a crisis did not happen again.

He said recent expansion, notably⁵ in the financial sector⁶, was not sustainable.

And he said it wasn't sustainable for long term prosperity to have a small number of individuals seeing higher pay while families saw their incomes drop.

He added that the Federal Reserve would continue to take the "necessary steps to unclog（清除油污） the financial markets and strengthen the economy."

Data

The data from the Commerce Department showing a fall in retail sales came after retail sales rose by 1% in January and by 0.3% in February, driven by heavy discounting.

The fact that Easter fell in March last year but in April this year also affected⁷ the figures, as the traditional boost in Easter spending was not reflected.

"We were expecting improvement and we got a huge decline. The report was weak across the board," said Jacob Oubina at Forex.com.

Such figures add to concerns that the worst of the economic crisis might not yet be over.