The coronavirus outbreak will have a major impact on economic growth worldwide this year, the Organisation for Economic Co-operation and Development (OECD) warned Monday as it lowered its global GDP forecast by half a percentage point to 2.4 percent, the lowest rate since the 2008-09 financial crisis.

That forecast assumes the virus outbreak fades this year, but a more severe outbreak "would weaken prospects considerably," the group of free-market economies said.

Already the global economy risks an outright contraction in the first quarter, the OECD said, in its first comprehensive study of the impact on the world's major economies.

Stock markets plummeted worldwide last week as investors fled to bonds and other safe havens on fears that consumer and business spending will freeze up as the virus spreads, curtailing corporate profits.