US and European Union trade negotiators said Friday they had begun to identify key areas of agreement and difference as they closed the first week of talks to create an ambitious transatlantic free-trade zone.

But despite controversy over US spying on its European allies that clouded the launch of the talks, there were few signs of initial friction in the discussion on the Transatlantic Trade and Investment Partnership.

"It's been a very productive week," EU chief negotiator Ignacio Garcia-Bercero said in a press conference.

"The main objective has been met: we had a substantive round of talks on the full range of topics that we intend to cover in this agreement. This paves the way to for a good second round of negotiations in Brussels in October."

"Negotiators identified certain areas of convergence across various components of the negotiation and -- in areas of divergence -- began to explore possibilities to bridge the gaps," he said.

His US counterpart, Dan Mullaney, said the talks were "very positive."

The talks opened Monday under pressure to reach agreement by late next year. Leaders from both sides agreed to aim for a pact before a new European Commission takes office in November 2014.

Asked about the deadline, Mullaney would only say that the two sides agreed to "move expeditiously" toward a deal.

The talks aim at removing bureaucratic, regulatory and protectionist barriers to more open trade and investment, to create what would be the world's largest free-trade area, involving 820 million people.

Both sides hope that by bringing down restrictions on trade and investment -- most of which involve non-tariff barriers rather than trade tariffs, which are already low -- will help generate jobs and boost economic growth.

Mullaney said there was no mention this week of the spying furor which almost scuttled the opening of TTIP negotiations.

France had called for a delay in the wake of disclosures that the US National Security Agency has not only been vacuuming up huge quantities of phone and Internet data but also snooping on its allies.

To avoid stalling the talks, separate US-EU discussions on the NSA activities were held quietly this week at the Department of Justice.

Key focuses of the TTIP negotiations include agricultural trade, cross-border investment, intellectual property rights and regulatory harmonization.

The "areas of divergence" that Garcia-Bercero referred to could involve red-line issues the US and Europe set out before the talks began: US banking regulations, and France's protections for its film and television industry.

France demanded that its audio-visual industry protection be off the table in the TTIP talks, and they were excluded from Garcia-Bercero's negotiating mandate.

Asked if that specific topic was raised this week, Mullaney replied that, in the area of services trade -- which includes the arts -- they "did cover the waterfront pretty much," without being any more specific.

Farm trade and "sanitary and phytosanitary measures" (SPS), which cover food safety, were an important part of the opening week of talks.

Washington, for instance, is pushing Europe to open up to US biotechnology products like genetically modified foods, which many European consumers consider dangerous.

And Europe remains unhappy over the US ban on its beef and veal exports, blocked for years since the "mad-cow disease" crisis.

"We did devote considerable time during this week to these issues, and that will continue to be a focus," Mullaney said.

"We are committed to address these SPS issues and SPS barriers."

The week was marked by an entire day devoted to discussions with US industry representatives worried and hopeful about the negotiations, and a briefing for US legislators also concerned on how a treaty would impact their constituents.

The next round of talks was scheduled for the week of October 7, in Brussels.