BAE Systems has reached another landmark in the development of the Eurofighter Typhoon plane.

The specialist defence company announced agreement in principle with the Ministry of Defence (MoD) on the UK share of production on the second stage of 236 aircraft.

Support from the three other partner countries of Italy, Germany and Spain is still needed, with contractual agreements expected soon.

At the same time, BAE Systems said the development was among factors expected to underpin a modest performance improvement this year.

Delivery of the UK's first batch of 55 Eurofighters is taking place with a view to full RAF operational deployment in 2006 or 2007.

In its update, BAE said it had agreed programme changes with the MoD on the first planes, which have been part-built at the company's Lancashire sites of Warton and Samlesbury.