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LONDON, June 20 (Reuters) - Britain should set a date for halving the time it takes to settle a stock trade - and stick with it, U.S. Securities and Exchange Commission Chair Gary Gensler said on Thursday.
Britain has said that UK stock markets should halve the time it takes to settle a trade on the London Stock Exchange and other platforms by the end of 2027, at the latest, to match Wall Street's move last month to complete a stock trade within one business day (T+1).
Canada and Mexico also shifted to T+1 last month to cut risks in markets and save on trading costs.
The European Union has said that moving from T+2 to T+1 is a matter of when, rather than if, and some industry officials want Britain and the EU to synchronise the shift given the markets are interlinked.
Gensler told an event in London held by UK Finance, a banking industry body, that the U.S. move cut the average amount of margin required by clearing houses by 25% to 30%, equivalent to about $3.8 billion, in first two days.
Furthermore, the rate of failed settlements did not go up, confounding predictions, Gensler said.
"It went smoothly," Gensler said, via video-link.
Among the key lessons is a prior need for same-day affirmation of trades, Gensler said.
"I wouldn't shy away from saying how important it is to just set a date and stick with it," Gensler said.
"Until you do that, it still becomes a lot of discussions."
If Britain took the same amount of time between plans and implementation as the United States, it would point to a UK shift mid 2026, Gensler said.
Charlie Geffen, who headed a government-commissioned report on moving to T+1 in Britain, said there was "no mad rush" to finalise details on the shift, as views will evolve.
"But it is essential to maintain momentum, 2027 is a no later than date," Geffen said.
"We have now got a clear policy and clear deadline. If I worry about anything, I think it's that... you run out of momentum," Geffen added.
The move to T+1 is seen as a precursor to same day settlement for stocks, already in place in China for A shares.
