In Germany, the documents are only available in the US embassy in Berlin. Known as "consolidated texts," they can contain the positions of both Brussels and Washington on key aspects of the Transatlantic Trade and Investment Partnership (TTIP).

Access to the embassy reading room has been limited to 139 German government officials cleared by the Ministry for Economic Affairs. National parliamentarians do not have access under the current process, according to the US embassy's German-language website.

The German parliament is chafing under the restrictions. Even Chancellor Angela Merkel's center-right Christian Democrats, who support strong trans-Atlantic relations and generally favor a trade agreement with the US, have grown critical. Norbert Lammert, president of the Bundestag, warned this week that parliament would not approve an agreement if it wasn't given greater oversight during the negotiations.

"I see no chance that the Bundestag would ratify a trade agreement between the EU and the USA without involvement in how it came together or any say regarding alternatives," Lammert said.

According to Daniel Hamilton, the executive director of the Center for Transatlantic Relations at Johns Hopkins University, Washington is concerned that providing greater access to the draft documents will result in leaks that could undermine the negotiations before a text is finalized.

"The real answer here is that in the end TTIP will be a mixed agreement in EU jargon, which means all member-state parliaments plus the European parliament will have to approve it," Hamilton told DW.

"So 29 different parliaments will have to approve this," he said. "They will have full access to everything obviously once they get that far, but they're not that far."

'Disenchantment with the EU'

The US position has softened somewhat. Until May, the consolidated texts weren't available in the EU member states at all. There was a reading room at the US mission in Brussels where cleared officials could view the draft documents.

Under pressure from the member states, Brussels negotiated with Washington to make the documents more accessible. The two sides agreed to set up reading rooms in US embassies throughout the EU. The current arrangement is based on the practice in Washington, where select officials are given clearance to read draft trade documents in secured rooms.

"There's been a lot more transparency than we've had in the past," Joseph Quinlan, an expert on trans-Atlantic economic relations and chief market strategist at US Trust, told DW. "You can't show the world your cards and not expect the people you're negotiating with across the table not to know what your cards are. There's a fine line there."

Many believe the process is still too opaque. According to the daily Tagesspiegel, those officials who have been cleared can only access the reading room two at time, twice a week, for two hours each session. And they can only use a pencil, pen and paper to take limited notes, the daily says.

Some organizations have taken matters into their own hands. Wikileaks has offered a 100,000-euro ($110,090) reward for TTIP documents. There have been repeated Internet leaks to the investigative journalism platform Correctiv.org, based in Germany.

Wikileaks also wants access to the documents

In response, the European Commission temporarily allowed access only to the Brussels reading room over the summer, refusing to forward the consolidated texts to the national capitals. German Vice Chancellor Sigmar Gabriel - a cautious supporter of TTIP - criticized the move, calling it a "very regrettable step backward."

"There's disenchantment with the EU and the Commission broadly across Europe, and TTIP becomes an area in which they vent those frustrations," Hamilton said.

Strong German opposition

Limiting access to the consolidated texts may be fueling the anti-TTIP fire. In October, more than 150,000 people protested against the proposed trade agreement in Berlin, the largest demonstrations in Germany since the run-up to the Iraq war in 2003. According to a 2014 Eurobarometer poll, 39 percent of Germans support TTIP while 41 percent are against.

"There's a general sense in Germany that German standards are world class and that American standards simply aren't and that it's all about the American Übermacht coming over and steam rolling the European way of life," Hamilton said. "Without much substance behind that, it's kind of a gut feeling."

The opposition is more pronounced in Germany. In the other major EU states, clear public majorities support the trade deal - 65 percent in the UK, 50 percent in France, 58 percent in Italy, and 73 percent in Poland. But as the EU's largest economy and most populous country, the success or failure of TTIP will likely be decided in Germany.

"I don't think the [German] government nor the members of parliament who are pro TTIP have been very well organized," Hamilton said. "They have not tried to articulate the case why you want TTIP. The business community has been passive."

"Those criticizing have been well organized," Hamilton said. "They have a pan-European organizational structure and they are active. They have simply taken the initiative away from the proponents."