A report by Camiel Eurlings, a Dutch legislator, to be adopted by the European parliament's foreign affairs committee on Monday offers a foretaste of the complaints Turkey can expect.
"The European parliament ... regrets the slowing down of the reform process," the report said, pointing to what it called "persistent shortcomings" across a range of areas.
It mentions insufficient progress on freedom of expression and raises concerns over the lot of religious minorities, corruption, and violence against women.
The report also criticised the unusually high threshold for parliamentary representation, under which a party must score 10 per cent nationwide, making it hard for Kurdish groups to win seats in areas where they have a majority.
Eurlings said: "The report is a clear signal that if Turkey wants the process to be successful, the speed of reforms must be increased."
Ali Babacan, the chief Turkish negotiator, will be in Brussels from Wednesday to try to reassure the European Commission that Turkey is committed to pressing ahead with economic and political reform despite national elections due next year.
He will attend talks on the sensitive areas of justice and fundamental rights and meet Olli Rehn, the EU enlargement commissioner and other EU officials.
The Commission is due to issue its regular progress report on October 24. Rehn has urged Ankara to show tangible improvements in human rights legislation by then, not least to offset a likely negative finding on its behaviour towards Cyprus.
But article 301 of the penal code, which has been used to prosecute writers, journalists and intellectuals for "insulting Turkishness", is not on the parliamentary agenda.
"They are aware of the shortcomings and are of the [EU] timetable but they have a quite solid determination to deliver before the [commission's] October report"
A senior Turkish diplomat
Can Baydarol, professor at Istanbul's Bilgi University and an expert on Turkey's bid to join the EU, said: "It seems that there is no chance for the Turkish government to take any steps forward for amending or abolishing article 301 in the near future."
Time was too short and nationalist feeling too inflamed after a spate of bombings in tourist resorts and attacks on the security forces claimed by Kurdish separatists, he said.
The ruling centre-right Justice and Development party (AKP) is concerned with pushing through sensitive reforms, particularly ones touching nationalist sentiment, that could hurt it in next year's parliamentary and presidential elections.
A senior Turkish diplomat, who declined to be named, told Reuters: "They are aware of the shortcomings and are of the [EU] timetable but they have a quite solid determination to deliver before the [commission's] October report.
"However, political realities should also be balanced in a proper manner."
The commission's report will assess whether Ankara has met an obligation to open ports to ships from Cyprus, which Turkey does not recognise, under a protocol signed last year extending its EU customs union to the bloc's 10 new member states.
If it has not complied, an EU summit in December is likely to put at least part of the accession talks on hold.