A tunnel between Northern Ireland and Great Britain is among the proposals being looked at by ministers as part of a wide-ranging review of connectivity within the UK, the transport secretary has confirmed. Grant Shapps said the government was considering building a bridge or tunnel between Scotland and the island of Ireland. “One of the elements in that review is should we have some sort of fixed connection – that could be a tunnel, it could be a bridge – between, for example, Scotland and Northern Ireland, which is the closest crossing,” he told BBC Breakfast on Wednesday. “Actually it is odd in a sense that we don’t have a connection with another part of the United Kingdom, so it is looking at whether that is feasible or not.” The transport connectivity review is being carried out by the Network Rail chairman, Sir Peter Hendy, as part of Boris Johnson’s effort to improve UK transport links. Two engineering professors have been commissioned to lead a study into the feasibility of a bridge or tunnel, outlining its cost, timescale and the work involved. But some have claimed the prime minister is simply seeking a distraction and noted that his talk of bridging the Irish Sea follows similarly grandiose and ultimately undeliverable schemes he dreamed up while mayor of London. And experts have warned that the depth of the Irish Sea and the presence of dumped munitions would cause problems. Shapps rejected a claim by the Scottish first minister, Nicola Sturgeon, that money could be better spent than on building a link between Scotland and Northern Ireland. He told the BBC: “I understand that it is not the responsibility of the Scottish first minister to connect the United Kingdom together. The Scottish first minister doesn’t even believe we should be in a united kingdom. So I understand her perspective but I think it is wrong. “For example, if you live in Northern Ireland, you want to know that you can reliably get the hauliers and lorry drivers in with goods from the mainland of the British Isles. Why would you ever be against connecting different parts of our country in a better way? It shouldn’t be a controversial thought at all. “As one small part of this union connectivity review [we will] undertake a study of the feasibility of doing that and we will report back in the summer.” Shapps said any fixed link between Scotland and Northern Ireland was more likely to be a tunnel than a bridge. He told BBC Radio 4’s Today programme: “I imagine that you would need to do a tunnel because of weather factors. “What we are talking about here is bridging or tunnelling a distance from here to France where notably we have built a tunnel.” He added that he did not think it should be controversial and would be a good idea “to make sure all parts of the United Kingdom are connected together as easily as possible”.