German Chancellor Angela Merkel attends a news conference after the EU summit in Brussels, Belgium, April 29, 2017. REUTERS/Christian Hartmann

BERLIN (Reuters) - German Chancellor Angela Merkel’s conservatives have widened their lead over the centre-left Social Democrats less than five months ahead of a federal election in Europe’s largest economy, according to an opinion poll.

The survey by the INSA institute, to be published Wednesday in the mass-circulation Bild newspaper, showed support for the conservatives unchanged at 34 percent while the SPD inched down 1.5 percentage points on the week to 28.5 percent.

The right-wing Alternative for Germany (AfD) fell one percentage point to 9 percent while the far-left Linke gained one percentage point to 10.5 percent. The Greens stood at 6.5 percent and the pro-business Free Democrats (FDP) at 7 percent.

The survey of 2,035 people was carried out from April 28 to May 2.