When the G20 leaders met in Hangzhou, Zhejiang province, in early September, the message was delivered to British Prime Minister Theresa May and European leaders that it would be in the interests of everyone if the divorce of the United Kingdom from the European Union proceeded smoothly.

It seems that the EU and the UK leaders have failed to heed that message.

About 100 days after the referendum in the UK on whether the county should remain a member of the EU or leave it, senior officials of both sides are squaring up to each other over the terms of the divorce. For example, EU leaders have since met twice, without a British presence, and insist that the ball is now in the UK's court. It is up to London, they say, to press the exit button.

Brussels now looks determined to "punish" the first-ever member to leave, even as the bloc is in the process of accepting more countries as members. Such hostility is perhaps understandable as the UK has shown the EU the cold shoulder, but an unexpectedly disruptive division is emerging and producing growing uncertainties.

Even though May announced on Oct 2 that her government would be evoking Article 50 of the Lisbon Treaty - the exit button - by March, the EU has refused to do more preparatory work, and as a result turbulence has again dominated the foreign exchange market, and the value of the British pound has again plummeted.

Such adversarial mentalities in the tough negotiations of the scheduled two-year divorce process will easily play into the hands of speculators. Clearly, more fluctuations and shocks are on the way if the EU and the UK maintain this kind of hostility toward one another.

And such a scenario will surely damage the global economy, which still lacks the proper impetus to grow.

Shada Islam, policy director of Friends of Europe in Brussels, has written that Europe is "playing with fire" and called for the two parties to show wisdom, vision and patience in their lengthy divorce.

Islam is absolutely right. Brussels is being short-sighted and conservative when it really needs to be bold, radical and visionary. That is the only option facing Brussels if it wants to avoid the markets losing confidence in Europe, and investors and travelers being frightened away.

Most importantly, Brussels needs to sit down quickly with London "amicably". It must adjust its mindset. It is true that being tough is reasonable if it wants to warn other members not to follow in the steps of the UK. However, Brussels and London need to consider carefully how to deal with one another, for they must live under the same roof, even though they are getting divorced. As a Chinese saying goes neighbors can relocate, but a neighboring country cannot.

So Brussels, which has already put the teams in charge of the talks in place, should engage London as Prime Minister May has suggested so preparatory steps for their split can be made in a friendly atmosphere.

The teams should conduct such negotiations behind closed doors, in order to avoid a vicious chain reaction among the media, markets, rating agencies, opinion leaders and the public.

Of course, if the two sides could consider separation and a remarriage at the same time, that could decrease much of the unnecessary side-effects for the world.

Since the 2008-09 financial and debt crisis, which originated in the United States and Europe, the world has experienced repeated shocks and growing uncertainties. It is time for British and EU politicians to show their competence, wisdom and flexibility and limit the shocks and uncertainties of Brexit by talking amicably about what comes next.

The author is deputy chief of China Daily European Bureau.

fujing@chinadaily.com.cn