In a move of considerable boldness, seven members of Libya's new Presidency Council arrived in Tripoli on Wednesday and established themselves at a naval base in the heart of the rebel-controlled city. Led by prime minister-designate Faiez Serraj, the politicians were brought by two Libyan patrol craft from Tunisia where the UN-backed Government of National Accord has been operating. Elements of the Libyan navy are clearly backing the Presidency Council. So too are a number of militias which have broken away from the Libya Dawn rebels who control Tripoli. The approaches to the naval port are heavily guarded by pro-Serraj militiamen some with tanks. The rebel National Salvation government of Khalifa Ghwell remains defiant. On Wednesday evening Ghwell told Serraj to get out or be arrested. It seems clear that such an arrest could not happen without a fight. Already rival militias have been exchanging fire. In the city's main Martyrs' Square a small demonstration led by a pro-Libya Dawn leader was broken up by another militia. Ghwell had endeavored to stop Serraj's arrival by closing Tripoli's surviving airport which is controlled by a militia leader who has favored the Government of National Accord. Earlier this week there were rumors, possibly spread deliberately, that members of the Presidency Council had arrived at a tourist resort called Palm City, well to the east of the capital. Serraj's arrival by sea right in the center of Tripoli appears to have caught the remaining Libya Dawn rebels by surprise. Serraj and his colleagues have the backing on the United Nations, the Americans and the Europeans. The EU has a €100 million emergency aid package to give to the new government. But there is a problem. The Libyan Political Agreement hammered out over a year, largely in the Moroccan resort of Skirhat, requires the elected parliament, the House of Representatives, currently in Tobruk, to endorse the GNA as well as an amendment to Libya's temporary constitution that would transfer control of the military, central bank and the National Oil Corporation to the new government. That approval has not yet been given, because there has never yet been sufficient members of parliament to pass the measures. HoR president Ageela Saleh has been urging a proper attendance. He, however, has always insisted that a vote cannot take place without his presence and on several occasions in recent months, he himself has discovered pressing foreign trips that meant he could not be in the parliament. The international community has understandably become exasperated at what it suspects is bad faith by Saleh and some leading HoR members. But without that vote, the government of Abdullah Thinni appointed by the HoR after free elections in the summer of 2014 technically remains in power. The pressing need for foreign governments is to be asked by Serraj to intervene against Daesh (the self-proclaimed IS) which is now well established in a 200-mile coastal area around Gaddafi's old home town of Sirte. IS forces are also battling but slowly losing to HoR-appointed army general Khalifa Hafter in bitter street fighting in Libya's second city, Benghazi. Worse, IS terrorists have been infiltrating Tripoli. Serraj is, therefore, faced with a toxic mix of forces for and against change while, without the HoR's approval, his international sponsors are caught in a legal trap. Nothing about Libya is ever simple.