Jerusalem — Israel is constructing a road through the West Bank, east of Jerusalem, that will allow both Israelis and Palestinians to travel along it — separately.

There are two pairs of lanes, one for each tribe, separated by a tall wall of concrete patterned to look like Jerusalem stones, an effort at beautification indicating that the road is meant to be permanent. The Israeli side has various exits; the Palestinian side has few.

The point of the road, according to those who planned it under former Prime Minister Ariel Sharon, is to permit Israel to build more settlements around East Jerusalem, cutting the city off from the West Bank, but allowing Palestinians to travel unimpeded north and south through Israeli-held land. “The Americans demanded from Sharon contiguity for a Palestinian state,” said Shaul Arieli, a reserve colonel in the army who participated in the 2000 Camp David negotiations and specializes in maps. “This road was Sharon’s answer, to build a road for Palestinians between Ramallah and Bethlehem but not to Jerusalem. This was how to connect the West Bank while keeping Jerusalem united and not giving Palestinians any blanket permission to enter East Jerusalem.” Mr. Sharon talked of “transportational contiguity” for Palestinians in a future Palestinian state, meaning that although Israeli settlements would jut into the area, Palestinian cars on the road would pass unimpeded through Israeli-controlled territory and even cross through areas enclosed by the Israeli separation barrier.

The vast majority of Palestinians, unlike Israeli settlers, will not be able to exit in areas surrounded by the barrier or travel into Jerusalem, even into the eastern part of the city, which Israel took over in 1967.

The road does that by having Palestinian traffic continue through underpasses and over bridges, while Israeli traffic will have interchanges allowing turns onto access roads. Palestinians with Israeli identity cards or special permits for Jerusalem will be able to use the Israeli side of the road.

The government of Prime Minister Ehud Olmert has recently made conciliatory gestures to the Palestinians and says it wants to do what it can to ease the creation of a Palestinian state. But Mr. Olmert, like Mr. Sharon, has said that Israel intends to keep the land to the east of Jerusalem.

To Daniel Seidemann, a lawyer who advises an Israeli advocacy group called Ir Amim, which works for Israeli-Palestinian cooperation in Jerusalem, the road suggests an ominous map of the future. It is one in which Israel keeps nearly all of East Jerusalem and a ring of Israeli settlements surrounding it, providing a cordon of Israelis between largely Arab East Jerusalem and the rest of the West Bank, which will become part of a future Palestinian state.

In a final settlement, Israel is expected to offer the Palestinians land swaps elsewhere to compensate.

The road will allow Israeli settlers living in the north, near Ramallah, to move quickly into Jerusalem, protected from the Palestinians who surround them. It also helps ensure that the large settlement of Maale Adumim — a suburb of 32,000 people east of Jerusalem, where most of its residents work — will remain under Israeli control, along with the currently empty area of 4.6 square miles known as E1, between Maale Adumim and Jerusalem, which Israel also intends to keep.

For the Palestinians, the road will connect the northern and southern parts of the West Bank. In a future that may have fewer checkpoints, they could travel directly from Ramallah north of Jerusalem to Bethlehem south of it — but without being allowed to enter either Jerusalem or the Maale Adumim settlement bloc. “To me, this road is a move to create borders, to change final status,” Mr. Seidemann said, referring to unresolved issues regarding borders, refugees and the fate of Jerusalem. “It’s to allow Maale Adumim and E1 into Jerusalem but be able to say, ‘See, we’re treating the Palestinians well — there’s geographical contiguity.’ ” Measure it yourself, he said. “The Palestinian road is 16 meters wide,” or 52 feet, he added. “The Israeli theory of a contiguous Palestinian state is 16 meters wide.”

Khalil Tufakji, a prominent Palestinian geographer, says the road “is part of Sharon’s plan: two states in one state, so the Israelis and the Palestinians each have their own roads.” The Palestinians, Mr. Tufakji said, “will have no connection with the Israelis, but travel through tunnels and over bridges, while the Israelis will travel through Palestinian land without seeing an Arab.”

In the end, he said, “there is no Palestinian state, even though the Israelis speak of one.” Instead, he said, “there will be a settler state and a Palestinian built-up area, divided into three sectors, cut by fingers of Israeli settlement and connected only by narrow roads.”

Asked for comment, David Baker, an Israeli government spokesman, said: “The security arrangements on these roads are in place to protect the citizens of Israel. And they are not connected to any other matter.”

A spokesman for the Israeli military’s civil administration department pointed out that Palestinians with permits to enter Israel could use the Israeli side of the road, and that for ordinary Palestinians, the road will be a quicker, better route from north to south than any current route.

There are numerous roads that only Israelis and Israeli-permit holders can travel on, but none segregated like this one.

E1 has been a key battleground in the struggle over control of Jerusalem. Some, like Martin S. Indyk, a former American ambassador to Israel now running the Saban Center at the Brookings Institution, argue that Israel should yield E1 to the Palestinians. “E1 is a critical issue in maintaining the territorial integrity and contiguity of the West Bank with East Jerusalem — it’s the only place where it’s possible to do that,” he said.

Israel has promised the United States that it will not build housing now in E1, freezing a plan to construct 3,500 homes. But Israel is completing a large, four-story police station on a commanding hill in E1, intended to be the main police headquarters for the West Bank, and it is laying down electrical and water lines for future development.

And it is building this road.

What is nearly finished now, awaiting the fixing of lights and the completing of tunnels and underpasses, stretches about 2.4 miles.

The road is currently open to the West Bank, but it cuts through the intended path of the Israeli separation barrier, which has not yet been built around E1 or Maale Adumim.

Presuming that the barrier will be completed, the road will be a kind of umbilical cord that cuts through Israeli-controlled and walled territory to connect the two parts of the West Bank. “Now there’s a big gap in the barrier between Azzariya and Shuafat,” of about 2.4 to 3 miles, “and Israel hasn’t started to build the fence around Maale Adumim,” said Mr. Arieli, the reserve colonel. “But this road will be the answer if and when Israel builds the fence around Maale Adumim. You see that Israel is creating the conditions for the future. They try to take advantage of the current situation to prepare the infrastructure for the right time to start building E1.” Mr. Seidemann believes that Mr. Olmert, facing many problems now, will not start building in E1, but that the leader of Likud, Benjamin Netanyahu, if he is elected prime minister, might do so. Mr. Netanyahu said in 2005 that he would build in E1 no matter what Washington thought.

Micaela Schweitzer-Bluhm, a spokeswoman for the American Consulate in Jerusalem, repeated American policy that Palestinians should be allowed to travel more easily through the West Bank “consistent with the need to maintain security.” Asked if this road predetermines final status, she said, “The U.S. government has encouraged the parties to avoid any actions that would predetermine permanent status,” but said she was not authorized to comment more specifically.

Mr. Tufakji said he had become cynical about the way Israel builds for the future it defines, no matter what it promises Washington. He sees a West Bank divided into three parts by Israeli settlement blocs, the most important of which are Maale Adumim and E1, around the capital that both peoples claim as their own. “Israel is building the infrastructure to keep E1, to surround Jerusalem,” he said. “They are working to have an area of minimum Palestinians and maximum Israelis.”