(AFP) - The murder of pro-European lawmaker Jo Cox will have a sobering effect on the final days of campaigning for Britain's EU referendum, analysts said Friday, as investors appeared more confident of a vote to "Remain".

Campaigning for the June 23 vote has been suspended following Thursday's fatal attack on the opposition Labour MP in her constituency in northern England, bringing a heated and divisive race to an abrupt halt.

"It has been a rather bitter campaign, with personality conflicts. It might calm people down in a more sober manner," Wyn Grant, professor of politics at Warwick University, told AFP.

Opinion polls suggest the referendum is too close to call, although two new surveys published in the hours before Cox died suggested Britain was on course to end its 43-year membership of the European Union.

John Curtice, professor of politics at Strathclyde University, said the "Leave" campaign in particular may now have to tone down its rhetoric, which had taken a strong anti-establishment tone.

"The argument is that the establishment says we can't leave," he told AFP, adding: "Attacking politicians won't be possible anymore."

He said: "The 'Leave' side may have to be a little careful with their language."

The Times newspaper concurred, noting: "That Ms Cox was a mother as well as a dedicated public servant means that attacks on the 'political class' or 'Westminster elites' are likely to be off limits."

However, Curtice said the suspension of campaigning could also hurt the "Remain" side, led by Prime Minister David Cameron, which needs time to regain the lead.

Both sides announced Friday that they would not hold any major events on Saturday, leaving them with just four days of campaigning left before a broadcast ban on polling day.

"It is not to the advantage of 'Remain' as they need any hour available to convince the undecided," Curtice said.

- Markets gain ground -

In Berlin, Chancellor Angela Merkel urged British politicians to moderate their language, warning: "The exaggerations and radicalisation of part of the language do not help to foster an atmosphere of respect."

London mayor Sadiq Khan, who is from the same party as Cox and also backs a "Remain" vote next week, said there was a need to "pause and reflect".

"I hope between now and 10pm on Thursday (when the polls close) the campaign is conducted in a different environment than it has been conducted up until now," he told LBC radio.

"We don't know the facts surrounding Jo's death. What we do know is there is a environment of hatred, of poison, of negativity, of cynicism."

A writer for the Conservative-supporting Spectator magazine, blamed the "Leave" campaign for raising tensions.

"When you encourage rage you cannot then feign surprise when people become enraged," wrote Alex Massie in an online article that quickly went viral.

The prospect of Britain leaving the EU had weighed on financial markets and sent the pound tumbling amid fears of the potential economic fall-out of a Brexit.

But European and Asian stock markets rebounded strongly Friday and the pound was firmer, lifted in part by expectations that Britain will now stay in.

"The suspension of campaigning for the UK EU referendum after the tragic death of Labour MP Jo Cox boosted risk appetite," said Nick Stamenkovic, an analyst at broker RIA Capital Markets.

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