A senior aide to David Cameron discussed Rupert Murdoch's takeover bid for BSkyB with a News Corporation lobbyist at a Downing Street meeting, the Guardian has learned.

Rohan Silva, a senior policy adviser in No 10, met News Corp's lobbyist, Frédéric Michel, on 2 December 2010 as the media conglomerate sought to take outright control of the satellite broadcaster.

An email about the meeting sent to James Murdoch said Michel and "David's adviser" discussed four different matters, including the "Sky transaction".

The correspondence was produced by Murdoch in his evidence to the Leveson inquiry last week, but it did not name the aide. Silva's position in Cameron's inner circle of advisers will increase pressure on Downing Street to give detailed assurances the prime minister had no involvement in the attempted BSkyB deal.

Downing Street said on Wednesday that any text or email exchanges between Downing Street and Michel over the BSkyB deal would be released if Lord Justice Leveson asked for them.

"Frédéric Michel has been into Number 10," confirmed the prime minister's spokeswoman. "We are not going to try and pretend otherwise and we don't think there is anything wrong with that."

A Downing Street source confirmed that Michel met Silva but said it was a routine meeting involving talks on intellectual property. On the BSkyB deal, they said Silva only stated the government's public position. Michel reported back to James Murdoch that Silva "recognised [the] need to look at it [the transaction] from a plurality point of view".

At the time, News Corp wanted to restrict UK regulatory scrutiny issues of "media plurality," which would have required the communications regulator Ofcom to make an assessment of whether the Sky takeover would give the enlarged company too much cross-media power.

Those opposing the transaction argued Ofcom should also consider competition issues as part of the plurality review and whether the deal would give the company too great a market share.

During December, the Murdoch company successfully kept competition issues out of Ofcom's remit, ensuring the subject was studied separately by the European Commission. It later concluded that the News Corp purchase of Sky created no competition problems, even though it amounted to the largest newspaper group buying the largest broadcaster.

Downing Street said the meeting did not breach the Chinese wall between the prime minister's office and the culture secretary, Jeremy Hunt, who was empowered to decide on the proposed takeover.

Cameron has repeatedly said he had no involvement in consideration of the £7.8bn BSkyB deal which was due to be decided on by the culture secretary, Jeremy Hunt, in a "quasi-judicial" capacity. Hunt's special adviser, Adam Smith, resigned last week following the revelation of emails between him and Michel about the takeover bid which Hunt said was "inappropriate". At the weekend Cameron said he told James Murdoch at a private pre-Christmas dinner in 2010 that the deal would be dealt with "impartially, properly, in the correct way, but obviously I had nothing to do with it, I recused myself from it."

The Downing Street denied Number 10 "could have been feeding information to DCMS" about the what to do on the deal because of the Chinese wall and because "nobody in Number 10 was informed [about the deal]".