The evaluation commission of the world athletics governing body flew straight to other 2017 bidder Doha having been "impressed" by the UK's capital city, which plans to use the Olympic Stadium from the 2012 Games in six years' time.
The athletics track was laid at the stadium on Monday but a row had threatened its existence after the Olympics with Premier League football club Tottenham Hotspur seeking a judicial review on the decision to grant West Ham United the use of the stadium.
Unlike Tottenham, West Ham have agreed to keep the athletics track and British double Olympic 1,500 metres champion Coe was happy the IAAF had been convinced.
"The Tottenham issue is an irrelevance and it was made very clear to the IAAF that is was an irrelevance," he told Reuters in a interview overlooking London's Tower Bridge.
"Not my words but the words of the chairman of the evaluation commission - as far as he is concerned this is a issue that has been resolved. The track is there to stay."
Commission chief Bob Hersh told reporters he had been "concerned" about the issue before the visit but that they were satisfied with the assurances despite London having to ditch plans to host the 2005 championships several years ago.
Coe, who is also on the IAAF Council and will vote on who hosts the 2017 world championships, believes Britain's strong heritage in athletics could help them beat Doha even if the IAAF has tended to favour newer markets with recent hosts.
EXTRAORDINARY LANDSCAPE
South Korea's Daegu held this year's biennial event.
"It is really important that London presents its case as well as it can with all the clear advantages of bringing a world athletics championships into a city with a global reach that is unsurpassed and a sponsorship market that is pre-eminent," said Coe, instrumental in winning the Olympic bid.
"We are a country absolutely rooted in track and field, some of our biggest and most memorable Olympic moments have come from track and field."
The IAAF evaluation commission visited the Olympic Park, which before London won the Games vote was an industrial wasteland in a poorer area of the city.
"I take them round an Olympic Park, 95 percent of which in construction terms is now finished, you show them the extraordinary landscaping and you show them an area that many of them saw seven years ago because they were involved in the Olympic process as well," Coe added.
"When you suddenly show them a transformed landscape and the ambitions of young people being met in an extraordinary way, then I think that speaks volumes."
