UK broadcasters will be allowed to show adverts more often during films on TV, under rules being introduced by Ofcom.
It said commercials could soon be seen every 30 minutes when films were aired, instead of the current 45 minutes.
Restrictions on advertising during documentaries, current affairs and programmes on religion have also been cut under the new, more simple code.
Meanwhile the government has launched a consultation on TV product placement, which is currently banned in the UK.
Rules forcing a 20-minute interval between advertising breaks within a programme have also been scrapped.
Previously, the first and last breaks in a programme were often scheduled close to the beginning and the end of that show.
Ofcom said its research showed this annoyed viewers who would rather have an even spacing of adverts to help them engage better with programmes.
The new code, which comes into force on 1 September, follows the first stage of Ofcom's comprehensive review of advertising regulations.
Broadcasters will still not be allowed to show more than 12 minutes of advertising in any one hour.
But the second stage of the consultation will look at the amount of advertising and teleshopping allowed on TV, as well as the frequency of commercial breaks.
Findings of that consultation will be published in the autumn.
Meanwhile, Culture Secretary Andy Burnham launched a consultation document into product placement in the UK on Friday.
It follows a European directive which states EU members must prohibit product placement but that exemptions may be allowed.
The government said its initial view was not to change the current UK ban but the consultation will explore the possibility of overturning it.
"If, as some in the industry are saying, this is a crucial step for broadcasters, then the industry must marshal strong arguments and put forward a convincing case," Mr Burnham said.
The EU, as part of the same directive, has called on member nations to introduce common standards on video-on-demand services.
The government consultation will also ask how this can be best achieved in the UK.