President Barack Obama issued a presidential directive on Cuba Friday that seeks to institutionalize and cement his policy changes toward the island and encourage further engagement even after he leaves office.

His administration also released a sixth set of regulatory changes designed to enhance business and trade between the United States and Cuba. It ranged from serious business overtures to one that will become a favorite of U.S. travelers to the island: no more limit on how many bottles of rum and Cuban cigars they can bring back for personal use.

Obama called the presidential policy directive “another major step forward in our efforts to normalize relations with Cuba” and said it “takes a comprehensive and whole-of-government approach to promote engagement with the Cuban government and people and make our opening to Cuba irreversible.”

The detailed, 12-page document, which builds on and consolidates changes the administration has made since rapprochement between the United States and Cuba began in December 2014, is “the manual that will be used by various agencies” to guide them in their future relations with Cuba, said a senior administration official.

It supersedes any previous presidential directives on Cuba and would stand as U.S.-Cuba policy until it is replaced, said the official who added: “It takes a significant amount of time to develop a presidential directive.”

Republican presidential candidate Donald Trump tweeted earlier this week that he would “reverse Obama's executive orders and concessions towards Cuba until freedoms are restored.”

But, said the administration official, it seems unlikely a future U.S. president would try to close the U.S. Embassy in Havana, end regularly scheduled flights to the island or disrupt the increasing number of budding business partnerships with Cuba. To do so, the official said, would be “cutting against the grain of public opinion here in the United States.”

Susan Rice, the president’s national security adviser, noted Friday that the president’s directive came on the the anniversary of the day in 1962 when an American U-2 plane flying over Cuba photographed offensive nuclear missile sites, setting off the Cuban Missile Crisis. Although the crisis was averted, “mutual suspicion remained high” and relations were mired in hostility for decades, she said.

Rice said engagement is now the correct policy. “Already, we’re seeing what the United States and Cuba can accomplish when we put aside the past and work to build a brighter future,” she said during a speech at the Wilson Center.

The directive makes it clear the president would like to see the embargo lifted: “The United States government will seek to expand opportunities for U.S. companies to engage with Cuba. The embargo is outdated and should be lifted.

“My administration has repeatedly called upon the Congress to lift the embargo, and we will continue to work toward that goal. While the embargo remains in place, our role will be to pursue policies that enable authorized U.S. private sector engagement with Cuba's emerging private sector and with state-owned enterprises that provide goods and services to the Cuban people.”

It could be the final set of Cuba-related regulations issued by the Obama administration but a senior official said that further “refinements” are always possible. The changes take effect Monday when the regulations are published in the Federal Register.

One of the most significant rule changes is one that allows U.S. companies to negotiate binding contracts in Cuba, even in areas currently prohibited under the embargo. Such contracts or agreements would go into effect contingent on future U.S. approval such as lifting the embargo, said Augusto Maxwell, a lawyer at the Akerman firm.

The new rules also allow Cubans and Americans to engage in joint medical research and lift monetary limits on the amount of Cuban products Americans can bring back in their luggage for personal use. Currently the limit is $400.

Also gone is the restriction that travelers can come back with only a combined total of $100 of alcohol and tobacco products. They can pack as many bottles of Cuban rum and cigars in their bags as they like — as long as they are for personal use and they pay the duties and taxes that would normally apply.

There will no longer be monetary limits on such products purchased in third countries that come into the United States as accompanied baggage.

The Commerce Department also will allow online sales of consumer goods to Cubans without requiring U.S. companies to get a prior license. Asked what types of consumer goods Cubans would be allowed to purchase, a senior U.S. official responded: “Any type of consumer goods you could think of” from toothpaste to air conditioners, television sets and auto parts.

In a move that is expected to facilitate trade between the two countries, the Office of Foreign Assets Control also will lift a restriction that prohibited foreign ships from entering a U.S. port to load or unload cargo for a period of 180 days after calling on a Cuban port.

“These amendments will create more opportunities for Cuban citizens to access American goods and services, further strengthening the ties between our two countries,” said U.S. Secretary of Commerce Penny Pritzker. “More commercial activity between the U.S. and Cuba benefits our people and our economies.”

But Florida Republican Rep. Ileana Ros-Lehtinen said: “This latest round of regulatory changes, like the ones before it, will do nothing for the suffering Cuban people and will instead further enrich the coffers of Castro state-owned entities while crushing the hopes that 11 million Cubans have for freedom, democracy and human rights.”

The new rules also expand the opportunities for Cubans to receive grants and scholarships to study in the United States. Two new categories have been added. Cubans will be able to receive such grants not only for traditional educational and humanitarian purposes but also to pursue scientific research and religious activities.

The regulations streamline some previous trade authorizations and allow U.S. nationals to provide services to Cuba or Cuban nationals related to developing, repairing, maintaining and enhancing Cuban infrastructure in order to directly benefit the Cuban people. That means that a U.S. engineering or architectural firm could offer their services for projects in Cuba, said Maxwell.

The presidential directive and regulations came the same day that U.S. and Cuban delegations were meeting in Havana to discuss human rights.

Despite progress in the U.S.-Cuba relationship, Obama said that “challenges remain — and very real differences between our governments persist on issues of democracy and human rights — but I believe that engagement is the best way to address those differences and make progress on behalf of our interests and values. The progress of the last two years, bolstered by today's action, should remind the world of what's possible when we look to the future together.’’