Buses and coaches driving through the capital will now be required to meet new emissions standards as the second phase of the London Low Emission Zone comes into force today (7 July).

From today vehicles that do not meet the required emissions standard will face a daily charge of £200 to enter the Greater London area. The second phase also effects drivers of lorries weighing more than 3.5 tonnes.

The first phase of the scheme - which aims to cut harmful emissions from most polluting diesel engined vehicles - was introduced on February 4 for diesel-engined lorries over 12 tonnes.

Boris Johnson, the Mayor of London, said: "Londoners and visitors to our great city deserve to breathe air of the highest possible quality; not splutter on a smog of poisonous fumes belching from the exhausts of buses and lorries."

Transport for London is urging the operators of vehicles that may be affected to check their vehicles meet the standard.

Head of the London Low Emission Zone, Nick Fairholme, said: "The majority of vehicles affected by the second phase of the Low Emission Zone are already compliant with the scheme."

The Low Emission Zone operates 24 hours a day, seven days a week, every day of the year and covers most of Greater London. The Zone is the first scheme of its type in the UK and the largest Low Emission Zone in the world. Cars and motorcycles are not affected by the scheme.

Transport for London will give operators of vehicles that do not comply with the emissions standards a 28 day warning period to upgrade their vehicle, during which they will not be issued with a penalty charge.