North East Combined Authority) Stockton North Stockton South Each constituency is made up of wards. Four constituencies are held by the Conservative Party after the 2019 general election, up by three since the 2017 general election. This was expanded to five after the 2021 Hartlepool by-election. Labour hold the other two. Sedgefield's partial seat is also represented by a Conservative MP, as of the 2019 election. The two Middlesbrough seats have the largest majorities for either party. The Middlesbrough Constituency has a sizeable Labour majority whereas the Middlesbrough South and East Cleveland Constituency has a strong Conservative majority. Authorities Tees Valley Combined Authority has its headquarters at Cavendish House, Thornaby. The area has 5 borough councils, each council has a representative in the combined authority. The TVCA, amends the mayor's annual budget (by two-thirds majority). It does not have the power to block the mayor's directives. Mayors The Mayor of Tees Valley is a directly elected politician who, along with the Combined Authority, is responsible for the strategic government of Tees Valley. There are other mayors for the boroughs of Middlesbrough and Stockton-on-Tees. Hartlepool also had a Mayor from 2002 to 2013. The current Tees Valley Mayor is Ben Houchen. The Mayor is responsible for Tees Valley's strategic planning and is required to produce or amend a plan for each electoral cycle. Lord Lieutenants Two Lord Lieutenants (Durham and North Yorkshire) are appointed by the borough's ceremonial counties. Economy The following is a chart of the Gross Value Added to the UK economy by the Tees Valley Combined Authority region, aggregated by industry. Enterprise zone The Tees Valley Enterprise Zone is an enterprise zone which encourages industrial development. It was initiated by the local enterprise partnership Tees Valley Unlimited and its creation was announced by the government in 2011. At its launch, the zone contained 12 sites. Four of these sites offer enhanced capital allowances, aimed at large manufacturers. These sites are Wilton International and South Bank Wharf, both in Redcar and Cleveland, Port Estates in Hartlepool and New Energy and Technology Park in Billingham, Stockton-on-Tees. The remaining sites offer reduced business rates. In March 2015 the government announced that a thirteenth site is to be added, South Bank Wharf Prairie, aimed at oil and gas decommissioning business. Businesses Imperial Chemical Industries (ICI) operated here until the late 1990s on three chemical sites at Wilton, Billingham and Seal Sands. ICI