The phrase "able to agree or" is grammatically correct and can be used in written English.
It can be used when discussing the capacity or willingness to reach a consensus or mutual understanding in a conversation or negotiation.
Example: "The committee members were able to agree or compromise on the proposed changes to the policy."
Alternatives: "capable of agreeing" or "willing to concur".
One of the best features of the "debt ceiling deal" is that no one seems to be able to agree who won or who lost.
But whether negotiators at the WTO will be able to agree on anything – agriculture or otherwise – remains an open question.
Legislative leaders and the Governor have not been able to agree on what can or should be done about the statewide problem.
I think we are both able to agree strongly that the sale or auction (and even ownership) of illegally acquired fossils is a bad thing, and that people should not be party to the exploitation of the fossil resources and heritage of a country that specifically bans their collection, export and sale.
Neither side, however, has been willing or able to agree to rules of engagement to support their professed desire to enter into serious negotiations to conclude a peace agreement that meet each others' principle requirements.
This system of government has been widely studied by historians and anthropologists, who have not been able to agree if it was developed internally or imposed on communities.
"Otherwise we have another leaking bucket to refill and no one able to agree on the size of the bucket or the size of the holes".
(Or, alternatively, without being able to agree on a plausible negotiating position, which is a big part of the story as well).
In some areas, maybe, such as extradition and consumer protection, some countries or groups of countries may be able to agree on common rules.
The statement says the group wasn't able to agree on what, if any, applications might justify editing human embryos, sperm, or eggs for reproductive purposes.
