THE spire at the peak of Britain's tallest building has taken shape on a North Yorkshire airfield ahead of its installation in London.

Severfield-Rowen carried out a trial build of the 500 tonne structure which will top the Shard of Glass on land adjacent to its headquarters at Dalton, near Thirsk, where 700 people are employed.

The structure, comprising 800 pieces of steel, is now being installed 80 storeys above the ground in London, with completion due before Christmas, after which glazing will begin.

The latest milestone for the North Yorkshire firm, responsible for steelwork on numerous landmark buildings in the Capital, comes as an interim management statement yesterday revealed that its Indian joint venture, launched exactly a year ago, had continued to enjoy impressive growth.

Chief executive Tom Haughey said: "You only get one chance when you take big pieces of steel up to that height and we wanted to make sure it fits perfectly so we have been doing trial assemblies at the yard next to Dalton.

"They are the actual pieces we will use. What we do is break them back down into manageable components, then take them down to London and reassemble them into pieces that can be lifted by a crane.

"There are always challenges and the biggest challenge isn't in making the steel it is always in the installation at that height.

"We are doing the installation in London now and it should be finished in the next few weeks, subject to the weather not being windy or foggy. It is a great moment for the company."

The interim statement released yesterday revealed that the firm's Indian joint venture with the country's JSW Steel, had an order book standing at £61m, compared to around £41m in August.

The 50/50 joint venture with the subsiduary of India's third largest steel producer, the Jindal Group, opened its plant in Bellary, Karnataka, a year ago this week with an initial order book value of just over £10m.

Mr Haughey said: "We are making very good progress in India. We are a bit ahead of where we would expect to be."

Although its UK order book stands at a healthy £230m Mr Haughey emphasised that the overall British market was still not in "great condition" with two of the firm's competitors having gone out of business in recent weeks.

He said the company remained cautious about the market outlook in the UK and continued to plan on the basis of subdued demand and relatively tight pricing.

The firm has also negotiated new banking facilities with Royal Bank of Scotland and Yorkshire Bank, that include a £50m revolving credit facility for five years, to November 2016, compared to a £40m, three year facility which was scheduled to expire in March 2013.

As well as the Shard the firm, employing a total of 1,100 staff across four UK manufacturing sites, has worked on a number of iconic London structures including the Leadenhall Cheesegrater tower, venues for the 2012 Olympics, including the main stadium, the Emirates Stadium for Arsenal Football Club, Wimbledon's Centre Court roof, and Heathrow's Terminal Five.