There has been much speculation about the Russian state gas company Gazprom's ambitions in the UK.
Medvedev said gas supply could not be used as a political weapon
In an exclusive interview with Panorama, the deputy chairman of Gazprom Alexander Medvedev said he is targeting "maybe 10% of the UK gas market in the 2010" including homes, business and factories.
When asked if Gazprom wants to take over the British gas supplier Centrica, Mr Medvedev said: "We are analysing different acquisition opportunities not only in the UK but also in other countries of Europe. Today I have no comment about the particular plans for Centrica but never say no."
Gordon Brown has indicated such an ambition could raise political issues.
Panorama asked if that worried Mr Medvedev.
He said: "No, I believe that it's an absolutely unreasonable discussion about the political side of the Gazprom supplies. We very often were accused that we will be in a position to use gas supply as a political weapon.
"I could tell you that it's not possible for two reasons. It's too costly to have such a weapon and we're investing billions and billions of dollars to increase our production capacity and to deliver gas to our customers.
"And another reason why it's absolutely absurd. It's two sides of the coin. Supply and demand. We are dependent on the export revenue from our supplies as much as our customers are dependent on our supplies. So it's a real partnership."
Panorama then asked if there would be repercussions if the UK did not allow such a takeover.
"I don't want to imagine such a nightmare situation which will mean the end of real capitalism" said Mr Medvedev.