A Turkish constitutional reform package to be submitted to parliament on Tuesday will make it possible for military top brass to be tried by a civilian court, media reported late on Monday, Reuters reported.
There was no immediate government confirmation of the reports, but such last minute changes to the draft amendments would likely boost tensions between the Islamist-rooted AK Party and the traditionally powerful military which sees itself as the guarantor of Turkey's secular order.
The main focus of the constitutional reform package has been changes to the way judges are appointed and making it more difficult to ban political parties.
Prime Minister Tayyip Erdogan says the changes will boost democracy in line with criteria laid down by the European Union for eventual membership.
But critics say the ruling AK Party has steadily increased the number of its sympathizers within the civil service since it came to power in 2002 and the new reforms would make it easier for it to ensure its supporters enter the judiciary too.
Making it harder to ban political parties, critics say, would also help Erdogan's AK Party against any future legal threat after it only narrowly escaped closure on charges of being a focus for Islamist activities in 2008.
Turkish markets are sensitive to tensions between the government and the military, especially after the detentions of dozens of retired and active officers late last month in an investigation into an alleged coup plot.
The final draft of the reform package would allow the chief of staff and top military commanders to be tried by a top state court, broadcaster CNN Turk reported, without citing a source.
Media reports said the AK Party had made an appointment with Parliamentary Speaker Mehmet Ali Sahin to submit the package at 11:00 a.m. (0800 GMT).
But parliament is unlikely to start debate immediately on the measures and voting is not expected until late April.
Financial markets have been unsettled by concern that political instability could result from a battle over the reforms, which are rejected by opposition parties in parliament as well as the judicial establishment.
Erdogan has warned he will call a referendum if the government fails to get the two-thirds majority needed in parliament to amend the constitution. That could further inflame political tensions and give the markets more jitters.
Strains have been building for weeks between the AK Party, whose roots lie in political Islam, and Turkey's old secular elites in the judiciary and military.