Amadeus held talks with Lufthansa last week over the airline's plans to introduce fees for bookings through GDSs.
The talks came after Lufthansa signed a deal with Sabre, another GDS, to exempt its agents from any payments under the carrier's Preferred Fares Scheme.
Lufthansa confirmed that it was in contact with others GDSs and that it will have "further discussions with them over the next weeks."
It confirmed that the Sabre deal had "created new consultations."
A statement from Amadeus, the dominant GDS in Germany, said: "Amadeus and Lufthansa met on 14 May to discuss the current situation initiated by the Preferred Fares programme and Amadeus is firmly committed to finding a solution.
"Amadeus is looking at all available options to safeguard the interests of its travel agency customers."
Under the preferred fares scheme launched by Lufthansa/SWISS, fares will go up by 15 one way and 30 for a round trip on tickets bought in Germany and Austria from July 1.
Prices for tickets bought in Switzerland and Liechtenstein will go up from October 1.
But the carriers said they would continue to make available the current lower fares after those dates.
These will be called "preferred fares" but will be subject to the surcharge if booked through a GDS.
Lufthansa will charge agencies 4.90 plus VAT per coupon and SWISS will charge CHF8 (5) per booking. It is this fee from which Sabre agents will now be exempt.
The scheme has angered agents in Germany who are due to meet with officials from the Bundeskartellamt, Germany's monopolies authority, next month.
Amadeus opposed the scheme when it was announced in January saying that there had been no consultation by Lufthansa.
The airline declined to give actual numbers for how many agents had signed up for its programme but said: "We have contracted with a large majority of agents."
US companies optimistic on travel
A large majority of US companies say they will travel as much if not more this year as they did in2007 despite the worsening economy.
The new survey by American Express Business Travel found that 83% of corporates planned to do the same number of trips or more as last year.
But because of the economy, 62% said they were looking for "procurement practices" to cut 5-15% off their travel spend.
A further 19% of companies were looking for even greater savings.
Amex's second annual Strategic Sourcery procurement practices survey also found that 67% of companies credited procurement practices with making savings in their 2007 budgets.
Frank Schnur, Amex's vp for advisory services, said: "Given today's industry and economic dynamics, companies are seeking out strategies to take advantage of savings opportunities without sacrificing the effectiveness or scope of their travel programmes.
"Travel is increasingly viewed as an investment, rather than a commodity to procure, and the partnerships and shared strategies created between procurement and travel departments are instrumental in maximising the value of corporate travel and entertainment budgets."
* 215 companies responded to the survey which was carried out by American Express and the US magazine Business Travel News.