NATO Secretary-General Mark Rutte said Wednesday that European allies are prepared to support the restoration of shipping through the Strait of Hormuz following a U.S.-Iran peace deal reached over the weekend. The deal is due to be finalized this week.

Speaking at a press conference, Rutte described the potential reopening of the strait, a critical waterway on the Persian Gulf through which about a fifth of the world’s oil passes, as a “massive step forward.” He said members of the military alliance, led by the United Kingdom and France, are ready to support the return of shipping through the strait.

Rutte said he welcomed President Trump’s agreement with Iran, which was reached over the weekend. The deal creates an opportunity to ensure that Iran never obtains a nuclear weapon, Rutte said. “The deal improves security for everyone,” he added.

The NATO chief also said many European members of the alliance are increasing investments in defense. As the U.S. has pulled back its contributions, other allies are stepping in to fill the gap, he said. NATO members are due to share responsibility more equally for the organization’s collective security, Rutte said, as the alliance needs more forces and a stronger industrial base.

The Pentagon has scaled back the forces it would send to Europe in a crisis, amid broader steps to shrink military support for NATO allies, The Wall Street Journal reported last month.