In one of the most explicit demands yet sent to an ally over Huawei, the United States government has told Germany to drop the Chinese company from its future plans or risk losing access to some US intelligence, The Wall Street Journal reports.

Huawei has faced accusations from the US that it could be used by the Chinese government for espionage. The company has repeatedly denied that it would act on behalf of China, and pointed out that the US government has not publicly produced any evidence to corroborate the claims, but US officials have remained unconvinced. The Trump administration has been pressing allies to end their relationships with Huawei, but Germany, moving ahead with its plans, has not moved to ban the company from its networks.

Letter from US Ambassador to Germany

According to the Journal, a letter sent from the US Ambassador to Germany warns the country that the US will stop sharing some secrets if it allows Huawei to work on its next-generation 5G infrastructure. The letter, according to the Journal, argues that network security can’t be effectively managed by audits of equipment or software. While the US plans to continue sharing intelligence with Germany regardless, the Journal reports, officials plan to curtail the scope of that information if Huawei equipment is used in German infrastructure.

In the US, the battle over the company has continued to escalate. The Justice Department has accused Huawei of stealing trade secrets, and its chief financial officer is facing extradition to the US on suspicion of violating sanctions against Iran. Huawei has denied wrongdoing, and last week, the company upped the stakes even higher when it filed a lawsuit against the US, arguing that a ban on its equipment in the government was unconstitutional.