Western donors want National Super Alliance leader, Raila Odinga, to rescind his withdrawal from the upcoming repeat election, even as they insist on respect for the IEBC.
The move by the Opposition last week may have surprised many of the envoys, after they had pressured both sides of the political divide to let the IEBC do its job and plan for elections.
However, Mr Odinga argued he and his running mate Kalonzo Musyoka were withdrawing from the race because the electoral agency had not heeded their call for reforms.
"We called on all actors to participate and respect the Constitution. We are reviewing the practical implications of this withdrawal," a senior diplomat from the European Union Delegation in Kenya told the Nation, suggesting the Supreme Court may be required to "pronounce itself on this matter."
"We regret this decision and we feel it would have been better if the Constitution, and the Supreme Court ruling, are respected."
Asked on possible sanctions, the EU official said his bloc were considering none at the moment, but said the EU sees a peaceful election as a better pathway to stability.
The EU has been indirectly supporting programmes at the IEBC. Through the UNDP, the European body, the UK and the US, they pumped about Sh500 million for programmes that range from training to civic education.
Recently, the UK called on all parties to ensure the presidential election is held according to the ruling of the Supreme Court.
"The UK has called for a free, fair and peaceful presidential election in Kenya in line with the constitution. We are disappointed by opposition candidate Raila Odinga's decision to withdraw from the contest scheduled for 26 October," a spokesperson at the UK High Commission in Nairobi said in a statement.
"We call on all parties to work together to ensure that democratic elections take place in line with the ruling by the Supreme Court. This is in the best interest of all Kenyans."
The UK maintained all parties must work within the Constitution and other Kenyan law warning "anybody engaging in or inciting violence should be held accountable by Kenya's institutions."
"We have been clear that the international community is watching Kenya and every step of its electoral process closely. Action should be taken against any individual engaging in or inciting violence. The UK reserves the right to take our own action at a later date, should it prove necessary, which includes considering the refusal or revocation of visas."
Last week, the US said it respected the decision by Nasa to move out of the race was within their right, but said it is regrettable.
"We respect the right of Nasa presidential candidate Raila Odinga and deputy presidential candidate Stephen Kalonzo Musyoka to withdraw from the Kenyan election scheduled for October 26, but we regret their decision to do so," US Ambassador to Kenya Robert Godec said.
"It is unfortunate that the IEBC and the political parties could not reach broad agreement on the conduct of the new poll."
Mr Godec maintained the US remains a neutral partner but said it viewed the election as "an extraordinarily important for the future of Kenya.
"We urge all Kenyans to come together to support their Constitution, their institutions, and to work for an election that is free, fair, credible, transparent, and peaceful. We stand with all Kenyans working to hold the best possible election and to deepen democracy, advance prosperity, and strengthen the security of their great country."
The diplomats from US, UK, EU, Germany and Australia had last week warned of unspecified sanctions against trouble makers.
They generally saw both the demands from Nasa and Jubilee as difficult to solve, given the tight schedule.
"Elections should happen as ordered. We had seen some demands from both sides as unreasonable," said the EU diplomat.
"Others are not, but then we have strict timelines by the Supreme Court."