A massive clear up is need at the site

Olympic chief David Higgins said no building work could begin on the East London Olympic Park until all the land needed is in public control.

He was speaking at a public inquiry into compulsory purchase orders on 306 hectares (756 acres) in Stratford.

About 90% is in public ownership, but many firms and residents are fighting eviction from the Lower Lea Valley.

Many people, fearing they are being short changed, are standing firm. A furious round of talks has cut the number of objectors from 404 to around 200.

Difficult site

A massive clear up will be needed before building work can begin in 2008, said Mr Higgins, the chief executive of the Olympic Delivery Authority (ODA), which is in charge of building the venues and infrastructure.

"There is a considerable amount of work to carry out, let alone work commencing on the major facilities," he told the inquiry in the Docklands.

"The timetable is extremely tight, and for the facilities to be completed for commissioning and test events from mid-2011, the land must be in the control of the LDA (London Development Agency) and the ODA by the summer of 2007 at the latest."

This land is currently split by canals and rivers and needing "significant remediation", he added.

9,000 new homes

Gareth Blacker, the director of development for the London Development Agency which must deliver the land for the Olympics, told the inquiry: "We are still negotiating with the other landowners in the Olympic zone and continuing to try and make agreements with them."

Apart from environmental and infrastructure boosts to the area, the Olympics will trigger a net gain of 4,500 permanent jobs and 9,000 new homes, up to half of which should be affordable, according to Mr Blacker.

Based on the evidence to the inquiry, inspectors will make a recommendation to the trade and industry secretary who will make a decision on the compulsory purchase orders.