In its monthly GDP estimates, the well-respected research group said that GDP may have grown by 0.1% in April and a further 0.1% in May.
The research comes as 11 out of 20 economists, polled by the Financial Times, believed that the decline in GDP had "paused" and predicted growth may return in the coming months.
Martin Weale, director at NIESR, told The Daily Telegraph: "So far, as we can say, the recession is over."
Vicky Redwood, an economist at Capital Economics, told PrintWeek that the economy had performed "surprisingly well" in recent months and agreed that we may be technically out of the recession.
However she predicted "sluggish growth" and said there would be a longer lag than is typical at the end of a recession, due to the continuing pressures on the banking sector.
The recession is over, leading think-tank claims
The recession is over, according to influential think tank the National Institute of Economic and Social Research (NIESR).
