The EU would allow a green lane for goods being imported into Northern Ireland from Britain as part of a "robust offer" to resolve difficulties over the Protocol, according to its chief Brexit negotiator Maroš Šefčovič.
However Mr Šefčovič, speaking at a Bloomberg event, said it would not be possible to do away with checks completely.
He also said that the EU will not negotiate on the basis of the Northern Ireland Protocol Bill currently going through the British parliament which he said is a breach of international law.
Under the offer made last October and fleshed out two weeks ago he said the EU had gone the extra mile.
The proposals would reduce sanitary and phytosanitary checks by more than 80%, cut customs paperwork in half, create a green lane for goods destined for Northern Ireland, simpler certification and allow the movement of goods that had been restricted such as chilled meats.
"This robust offer can work, and it can work fast," he said, pointing out that the medicines supply issue had been resolved.
However he warned that the EU has its limits.
"We must protect the integrity of the EU's Single Market and our consumers," Mr Šefčovič said.
"It is simply unrealistic – and unfair – for London to expect that all barriers can be lifted when goods move to Northern Ireland from the rest of the UK.
"On this, the UK government needs to be honest at home and respectful vis-à-vis the EU. Zero checks is not an option."
He said there could be an option of putting a sticker on goods destined for Northern Ireland.
However he said the pre-Brexit reality is no longer an option.
"I can bring as many solutions to the table as possible, and I have done so, but I cannot force political will on someone else’s behalf," Mr Šefčovič.