Guy Verhofstadt — waiting for David Cameron | EPA Verhofstadt wants a Cameron close-up Liberal group leader calls on British PM to debate Brexit in the European Parliament.

British Prime Minister David Cameron has been touring the continent to talk with other leaders about reform proposals aimed at avoiding a U.K. exit from the EU, and now some in the European Parliament are demanding a date on his itinerary.

Guy Verhofstadt, head of the assembly's centrist Alliance of Liberals and Democrats for Europe group, has asked Parliament President Martin Schulz to invite Cameron to a plenary session in Strasbourg in October or November to explain his vision for a reformed EU.

"The resolution of the U.K. problem concerning the current treaties and the danger of Brexit are still significant," Verhofstadt wrote in an email to Schulz, a copy of which has been seen by POLITICO. "Yet nowhere is a public and transparent debate being held."

Verhofstadt, a former Belgian prime minister, took aim at Cameron for claiming that the EU process isn't democratic enough while so far failing to initiate a debate with the EU's one democratically elected institution. Cameron has promised that Britain will hold a national referendum before the end of 2017 on the country's EU membership.

"David Cameron has often accused the EU of a democratic deficit. It would therefore be very strange for him to turn down an invitation to openly discuss his proposals," he said in a statement.

Cameron has been meeting with European leaders to float his ideas on a new relationship with the U.K., including more powers for national parliaments to block proposed EU legislation and curbs on immigration. The demands come as Euroskepticism grows in Britain, with complaints that freedom of movement within the EU has led to an influx of migrants.

Asked about the invitation, a spokesman for Cameron said: “Since the election the PM has spoken with the 27 other EU leaders, as well as senior figures from the European Parliament and other institutions, about his plans for renegotiation. Discussions will continue over the coming months and any invitation will be dealt with in the usual way.”

Verhofstadt's latest request for a parliamentary command performance from a world leader follows a July 8 appearance in Strasbourg by then-Greek Prime Minister Alexis Tsipras. After several invitations to speak to the assembly, Tsipras finally agreed to take part in a debate with European parliamentarians. In a much watched-down speech, he made an impassioned plea to the Parliament for a "sustainable" solution to the economic crisis.

The debate was held days after Greeks had voted in a referendum to reject the terms of a third bailout package. Verhofstadt's own fiery remarks during the debate became a viral sensation on the internet, with a YouTube video attracting millions of views.

Following Tsipras' visit, Verhofstadt called on Schulz to create an oversight committee dedicated to checking in with Greek authorities every two months to ensure that they are complying with reforms as dictated under the bailout agreement.

Verhofstadt's request for a plenary session with Cameron was also sent to other parliamentary group leaders, including Gianni Pittella of the Socialists & Democrats, Manfred Weber of the European People's Party and Syed Kamall of the European Conservatives and Reformists.

"Martin Schulz is entitled to invite David Cameron to address the European Parliament, and it is also the British prime minister's prerogative to decide when might be the right time to accept," said Kamall. "The British prime minister answers to the British parliament and the British people, not to Guy Verhofstadt."

A spokesperson for Schulz said the president would put the matter up for discussion Thursday in the meeting with group leaders. Schulz and Weber both met with Cameron and other U.K. ministers in June for talks on the Brexit issue.