London, May 21 (RHC)-- British Prime Minister David Cameron has warned that leaving the European Union (EU) would cost Britain billions of pounds in infrastructure investment deemed as an economic risk to the country.

Addressing pro-EU supporters at a campaign event in central England on Saturday, Cameron said that leaving the EU would have a 'devastating impact' on future major road, rail and education projects.

Cameron's remarks were made after the International Monetary Fund (IMF) said on Friday that if British voters decided to leave the bloc in a June referendum, it would be the biggest threat to the country's economy. Christine Lagarde, the IMF chief, said there were no economic positives to Britain leaving the EU and that the impact would range from "pretty bad to very, very bad."

The Bank of England had also said earlier that Brexit could push the world's fifth largest economy into recession. Opinion polls have indicated that UK voters believe staying in the EU would be best for Britain's economy, but that support for leaving and remaining still remains at a virtual tie.

The economy and the impact of a possible British exit, or Brexit, on jobs, wages and trade are a key battleground for both the "In" and "Out" campaigns before Britons vote on June 23 on whether to stay in the 28-member bloc.