BRUSSELS (Reuters) - It is still impossible to say if there will be a trade deal between the European Union and Britain before the deadline of Dec 31, a senior EU official said on Monday. Britain’s transition period after its exit from the European Union ends on Dec 31 and unless it negotiates a trade deal with the EU by then there will be tariffs and quotas on trade between Britain and the EU, hurting the economies of both. “Major obstacles remain on the three key issues,” the official said, referring to fisheries, state aid and future dispute resolution. “It is impossible to say if there will be a deal.” The official also said that Britain’s vote on Thursday in the House of Commons on the internal market bill and financial bill, which could undermine the existing treaty on Britain’s withdrawal from the EU, could hurt talks. “The internal market bill and financial bill in the Commons will not help the negotiations, to say the least,” the official said.