"It is remarkable that those calling for open access from BT are not willing to provide it themselves. We call on others to follow BT's lead in offering to open its infrastructure and content to all on a fair basis," BT said.
The ISP was referring to recent proposals from the Conservative Party that slammed a suggested 'broadband tax', under which Brits with a telephone line would fork out £6 per year to pay for the roll-out of 100Mbps broadband.
The ISP said it hopes to offer superfast broadband to five million Brits by spring 2011.
"Competition is a two-way street. We support Jeremy Hunt's [Shadow Secretary of State for Media] call for open access to all networks and call for others to follow our example and to open their infrastructure and services."
BT recently revealed it has been in talks with Ofcom since 2007 over the possibility of letting other ISPs access its infrastructure.
The telecom giant said it could go ahead with the plan, provided other ISPs also open up their infrastructures.
Virgin Media said its primary focus was developing its network and launching its own next generation products.
A Virgin Media spokesperson said: "We've invested over £13bn in ultrafast broadband in the UK, launched market-leading 50Mb broadband and have announced plans for 100Mb broadband by the end of this year."
"We're currently focused on delivering these ultrafast broadband services to more and more homes across the UK."