European Commissioner for Transport Siim Kallas said a Tallinn-Helsinki tunnel would not be feasible in the current economic situation.
"Considering how much tunnel safety standards have been raised, building and operating a tunnel would be terribly expensive," Kallas told Postimees, adding that he would not be opposed to the idea in principle.
The cost of building the tunnel has been estimated at around 4 billion euros.
The years-old idea was recently discussed at a conference hosted by the business daily Äripäev, where investor Joakim Helenius said a 80-kilometer tunnel connecting Estonia to its richer neighbor would resolve Estonia's economic woes, such as its small market, small workforce and poor access for travelers.
Helenius suggested funding could in large part be sought from the EU and Finland.