The German MEP is in London to meet the UK Prime Minister, as well as London Mayor Sadiq Khan.
On Friday, he will meet Labour party leader Jeremy Corbyn and will deliver a speech on "The EU and Britain: parting ways but working together" at the London School of Economics.
Ahead of the visit, Schulz spoke exclusively to this website, saying he will stress there will be "no negotiation without notification."
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The deputy said, "My visit to London is to get a pulse from the British authorities on the state of affairs on Brexit and EU-UK relations.
"This will be my first meeting with Prime Minister May."
Schulz said, "I will reiterate the principle of no negotiation without notification. I will also underline the importance for the European Parliament of upholding the four freedoms and will encourage an early activation of article 50, which is necessary to limit uncertainty."
The meeting with May will see the two leaders discuss Brexit as well as security and the future of economic policy in the EU.
But any developed position on the forthcoming Brexit negotiations is unlikely, as the EU's stance is, as he points out, to forgo any negotiations before Britain has formally triggered its exit.
Speaking separately last week, Schulz was asked if the British could be provided with access to the EU internal market without guaranteeing the right to the free movement of EU citizens.
He replied, "Certainly not. That is a red line for us in the European Parliament that is non-negotiable."
In the same online interview, he said, "The government in London apparently had no plan ready for an exit scenario - it was taken by surprise. That's why I can understand that they need a little time to get themselves sorted.
"But I hope that the petition is submitted by the end of the year. Once it is, the two years of negotiations can begin. The people, but also the economy, the companies, need to be able to plan."
Schulz was also present at last Friday's Bratislava summit, where he said leaders of EU member states must stop blaming the bloc for failures while taking credit for successes as they battle to save the union.
Schulz said: "The member states built the union and therefore the member states have to take responsibility for [what] they created."