LONDON (Reuters) - Britain's FTSE 100 share index .FTSE will dip in the months after the country starts official divorce proceedings later on Wednesday with the European Union but reach new record highs next year, a Reuters poll found.
Since June's shock vote to quit the EU, British shares have found support from a slide in sterling, resurgent commodity markets and a much better economic performance than had been feared, and the benchmark hit a record high of 7,447.0 in March.
"The FTSE has had a spectacular run since the Brexit vote, with the share prices of UK multinationals benefiting from the lower pound. In addition, the FTSE has benefited from a general uptrend in global stock markets since the U.S. election," said Colin Cieszynski, chief market strategist CMC Markets.
Global equities have rallied since Donald Trump was elected U.S. President in November, driven by a reflation trade on hopes for increased infrastructure spending and tax cuts.
But on Friday, Republican leaders pulled legislation to overhaul the U.S. healthcare system, a 2016 election campaign promise of Trump, which has led to questions about his ability to deliver on his other pledges.
Adding more mud to the water, there has so far been little clarity on the tone the Brexit negotiations will take. Prime Minister Theresa May is due to trigger Article 50 on Wednesday, starting the two-year countdown to Britain leaving the EU.
Come mid-year, the FTSE 100 will be at 7,250 points, down just over 1 percent from Tuesday's close of 7,343.42, according to the median forecast of 20 traders, fund managers and strategists. But once again, stock market watchers shrugged off any longer-term negative implications.
By the time 2017 comes to a conclusion the benchmark index will have roared back to 7,425, according to the poll, taken in the past week. It will then power through the previous high to reach 7,500 by end-June next year.
"It's not going to be the weakness of sterling -- we have seen the worst of the Brexit impact on the currency," said Jasper Lawler at London Capital Group.
"It's going to be more that the U.S. markets are massively overvalued and we are still in a general global bull market for equities. People have been worried about the impact of Brexit and steered clear, so that relative underperformance will be redressed."
Following the June referendum, Britain's economy has proved resilient -- at the end of 2016 growth accelerated -- but over the whole year it was weaker than previously thought, amid signs the Brexit vote will increasingly act as a brake.
Sterling is down around 15 percent against the dollar since the surprise outcome to leave the EU, making FTSE stocks cheaper for foreign investors and lifting repatriated profits.
"The recent slide in sterling has lifted the earnings of multinationals significantly since the Brexit referendum," said Alastair George, chief investment strategist at Edison Investment Research.
The pound's downward momentum is probably just about over, however, and with little hope for recovery, it will trade not far from current levels in the coming year, a Reuters poll found earlier this month. [GBP/POLL]
Cable has come under further pressure as the U.S. Federal Reserve has embarked on a monetary policy tightening cycle while the Bank of England is not expected to act until 2019 at least. [FED/R][BOE/INT]
Compared to European stocks, the FTSE will slightly outperform this year. The Reuters poll predicted the STOXX Europe 600 index would be up a little under 1 percent from current levels by the end of December. [EPOLL/FRDE]
Polling by Kit Rees and Helen Reid in London, Danilo Masoni in Milan; Editing by Catherine Evans