Chinese President Xi Jinping asked U.S. President Donald Trump for a 100-day grace period to deal with North Korea’s military provocations during their meeting in early April, according to several U.S. and Japanese sources.

At their talks in Florida, Trump asked Xi to strengthen economic sanctions against Pyongyang over its repeated ballistic missile and nuclear tests. China accounts for about 90 percent of North Korea’s foreign trade.

The U.S. president said that if Beijing did not cooperate, Washington was prepared to implement new sanctions against Chinese companies that have business dealings with North Korea, including several financial institutions, according to the sources.

Xi may have asked for the grace period to prevent such U.S. sanctions from making it difficult for the targeted Chinese companies to continue their business transactions with U.S. financial institutions and companies.

Sources said Xi indicated to Trump that Beijing would take stronger action to persuade Pyongyang to halt its military provocations, such as restricting transfers of funds from companies in China to North Korea as well as limiting petroleum exports to North Korea.

Both Trump and Xi agreed to implement independent sanctions in the event North Korea went ahead with a major provocation, the sources said.

At the summit, Xi and Trump agreed to compile a plan over a 100-day period to correct the trade imbalance between the two nations. The same deadline was apparently used for the national security issue.

The Chinese Communist Party plans to hold a meeting in autumn in which top-level personnel changes are expected. Party officials likely did not want to hold such an important political event amid strained relations with the United States.

In late April, Trump praised China’s efforts to help deal with North Korea.

But Pyongyang on May 21 launched another ballistic missile, casting doubts on the efficacy of the measures being taken by the United States and China.

Although there have been signs of a possible sixth nuclear test, North Korea has not gone ahead with that move.

U.S. officials apparently feel that Chinese pressure was behind North Korea’s apparent reluctance to conduct a nuclear test, and some have suggested a shift in U.S. strategy to one emphasizing dialogue.

U.S. Defense Secretary Jim Mattis, for example, on May 19 expressed a cautious stance toward immediate military action against North Korea.

The 100-day grace period asked for by Xi would end around the time the Group of 20 summit is held in Germany in July.

Trump and Xi would likely meet again on the sidelines of that summit to exchange views on how to deal with North Korea.