* London office prices could fall by 20% over two to three years, similar to the decline following the 2008 financial crash.

Negotiations with the EU are about to enter the final few weeks, and while May has said an agreement is 95% complete, crucial areas, including the fate of the Northern Ireland border, remain unresolved.

A no-deal Brexit would shorten the odds on a long UK recession Read moreA demand by EU negotiator Michel Barnier for a backstop that would keep the Irish border open to trade, even if that meant separating the province from the mainland and creating a border in the Irish sea, has been rejected by the prime minister.

The impasse has fuelled doubts that a deal can ever be agreed in what time is left before each side must seek ratification.

S&P Global Ratings credit analyst Paul Watters, said: “Our base-case scenario is that the UK and the EU will agree and ratify a Brexit deal, leading to a transition phase lasting through 2020, followed by a free trade agreement.

“But we believe the risk of no deal has increased sufficiently to become a relevant rating consideration. This reflects the inability thus far of the UK and EU to reach agreement on the Northern Irish border issue, the critical outstanding component of the proposed withdrawal treaty.”

Coming only a day after the chancellor said the failure to secure a deal would force him to hold an emergency budget, S&P’s analysis joins a welter of independent reports that forecast that a split from the EU without a deal will deala serious blow to the prospects of the UK economy. Last month rival agency Moody’s said the risks to the British economy had “risen materially” in recent months.

Failure to agree a deal with Brussels would lead to a sharp fall in the value of the pound, triggering higher inflation and a squeeze on real wages lasting for as long as three years, it warned.

Adding to the weight of opinion, the International Monetary Fund and and the OECD have also said that crashing out of the EU without a deal was a material risk to the UK, the EU and the global economy.

Sign up to the daily Business Today email or follow Guardian Business on Twitter at @BusinessDeskThe warnings are likely to be dismissed by leading Brexiteers as an extension of the Treasury’s “project fear”, which predicted steep falls in household incomes, house prices and inflation.

Jacob Rees-Mogg and Iain Duncan Smith told the chancellor ahead of the budget that he was being too gloomy about Britain’s economic prospects outside the EU, even if it meant coping with trade barriers at EU border posts.

Rees-Mogg argued that Britain’s economy would be set free by leaving the EU, and though he preferred a deal to secure frictionless trade, this would be counterproductive if it tied the UK to EU rules for many years.

But Britain’s national income has already grown more slowly this year than expected prior to the EU referendum, with GDP growth below its previous trend of 2% to 2.5% and with wages only just inching ahead of inflation this year.

S&P said leaving the EU without a deal would make matters much worse, pushing the UK into a moderate recession lasting between a year and 15 months, with GDP contracting by 1.2% in 2019 and 1.5% in 2020. After that, the economy would return to growth, it said, though the pace of growth would be moderate.

“By 2021, economic output would still be 5.5% less than what would have been achieved in a scenario with an orderly exit and transition period for the UK,” it said in its report, Countdown To Brexit: No Deal Moving Into Sight.

S&P said high street banks would be caught up in the downturn, though efforts to shore up their reserves over the last eight years would provide protection against rising corporate insolvencies and weaker house price values.

Housing associations would also come under financial pressure from a fall in house values. Meanwhile, insurers would need to plan for a downgrade in the UK’s credit rating, which would increase their borrowing costs.

Party of Democratic Action SDA – centre-right

Alliance for a Better Future of Bosnia and Herzegovina SBB BiH -centre-right

Croatian, Democratic Union of Bosnia and Herzegovina HDZ BiH – centre-right

Croatian Democratic Union 1990 HDZ 1990 – centre-right

Alliance of Independent Social Democrats SNSD – centre-left (though in reality, nationalist)

Serb Democratic Party SDS – right-wing

Party positioning is indicative and to be viewed in the context and framework of the country’s politics.

There are 10 candidates for the post of Bosniak member of the three-member Presidency. Croats will be choosing between four candidates, while there are three candidates for the Serb seat.

The 2010 electionThe last general elections in Bosnia and Herzegovina were held in 2010. Turnout was 56%.

The clear winner in Republika Srpska entity was the Alliance of Independent Social Democrats, SNSD, with 43.3%, nearly twice as much as the SDS. In the Federation, the Social-democratic party, SDP, and the Party of Democratic Action, SDA, won 26% and 19.5% of the vote respectively. The largest Bosnian Croat political force was the Croatian Democratic Union, HDZ, with 11%. A six-party government (between the Social Democratic Party (SDP), the Party of Democratic Action(SDA), the Croatian Democratic Union of Bosnia and Herzegovina (HDZ), the Croatian Democratic Union 1990, the Serbian Democratic Party (SDS), and the Alliance of Independent Social Democrats (SNSD)) was eventually formed 15 months after the election.

The outgoing government and parliament have been dubbed the worst ever. 106 laws were adopted by parliament in the past four years, down from the 180 between 2006-2010. As a comparison, over the same period the Montenegrin government adopted about 350 laws, Serbia 500 and Croatia about 750.

In the tripartite presidency vote, the SNSD candidate Nebojsa Radmanovic was the clear winner among Serb voters, while the SDA candidate Bakir Izetbegovic prevailed as the Bosniak member of the Presidency, and the SDP candidate Zeljko Komsic emerged as the Croat member of the Presidency. The latter result was not welcomed among several right-wing Croat parties who accused Komsic of being elected by Bosniak voters.

“>A reminder of the wars in former Yugoslavia at the Newseum in Washington D.C. Photo: Alberto Nardelli for The Guardian.A country’s constitution and institutions are always a consequence of its history. In Bosnia and Herzegovina, the divisions of the past may have been frozen, but their complexity and scars remain deeply enshrined in how the country’s parliament and loba negra epub government are elected and organised.