Veteran BBC journalist John Simpson planted the 500th tree on the streets of Marylebone last Thursday to mark the completion of a three-year project to line the pavements with greenery.

The W1W Tree Planting Initiative has seen the likes of TV presenter Matthew Wright, Marylebone resident Barbara Windsor and gardener Alan Titchmarsh all plant trees around the area since 2009.

The ceremony, outside BBC Broadcasting House on Hallam Street, saw Mr Simpson joined by his family, pupils from St Vincent’s Primary School and the newly elected Lord Mayor of Westminster, Cllr Angela Harvey.

Speaking at the event, the 67-year-old BBC world affairs editor said: “I cannot tell you how chuffed I am to be here. In fact when I received the letter I thought they must have thought I was David Attenborough, so I should get in there quickly before they realised who I really was.

“I cannot think of an honour that I have ever had which has given me such great pleasure.

“In my daily work I see a lot of destruction and cruelty and stupidity – a lot of the destroying of good things of the earth. To play a part in planting something like this is absolutely marvellous.”

Three years after Hallam Street played host to the first trees in 2009, dozens of Marylebone streets have now been lined with greenery.

While two-thirds of the funding for the project came from the Westminster Tree Trust and Westminster Council, �80,000 was donated by local residents, businesses and organisations.

Weymouth Street resident and W1W Tree Planting Initiative organiser Mark Gazaleh said: “I never thought that we would reach the 500-tree target.

“When we planted the first trees in 2009 I was really surprised by the support we received.

“I’m really proud that as a team we could produce something that the community liked so much.”