The union said that Ryanair was refusing to deal with two pilots it had nominated. Ryanair said it planned to operate all its flights.
Head of VCs' Industrial Department Ingolf Schumacher said: "In the history of the VC, there has never been a case in which the collective bargaining autonomy has been trampled on by an employer as it is now the case with Ryanair".
VC said all Ryanair flights at German airports will be affected.
However, the group cancelled the strikes after Ryanair's offer to talk about the trade unions' complaints, covering areas such as the carrier's strategy as well as pay and employment models in the fast-growing budget airline industry.
IMPACT had given the airline a midday deadline to provide formal recognition, saying that strike action could be renewed if an agreement wasn't delivered.
And the union added that the danger of strikes by Irish pilots had now receded for the time being.
Ryanair RYA.I has agreed to meet with German pilot union VC on January 5, a spokesman for the airline said on Thursday, hours after the union sent a memo to members telling them to keep their phones on for possible news on a strike.
Commenting on the official recognition of the union by Ryanair, IMPACT official Ashley Connolly described it as a "historic achievement" that would resonate beyond the company.
But it cautioned that it expected management to reach agreement on procedures quickly so that the parties could move on to negotiate "substantial issues" around pilots' pay and working conditions.
Until Thursday, Ryanair had essentially refused to recognize trade unions as representatives of their employees.
"We very recently received correspondence from Ryanair in response to the meeting we held on Tuesday evening", he said.
"Ryanair now need to provide answers on the fees and charges faced by cabin staff and set out how they ensure these staff are receiving the national minimum wage".
In a statement, Ryanair said it had sent a letter confirming that is recognising Impact and its Ryanair Company Pilot Council.
Earlier: Ryanair has until noon to come up with a document to satisfy pilots' union IMPACT.
The first meeting between company executives and a pilots union took place in Dublin on Tuesday.
The union said it was disappointed that management did not put its intention to recognise the union on a piece of paper.
"IMPACT said the company's confirmation that it recognised the union. and would conclude a comprehensive agreement, meant the danger of industrial action had receded for the present", it said in a statement.