HANOI, April 3 (Reuters) - Vietnam's Prime Minister, Pham Minh Chinh, pledged on Thursday to maintain the country's economic growth target of at least 8% for this year, despite the U.S. imposing a hefty 46% tariff on the Southeast Asian nation's exports.

The announcement came during an emergency cabinet meeting, which included Trade Minister Nguyen Hong Dien, Central Bank Governor Nguyen Thi Hong, Minister of Finance Nguyen Van Thang, and Deputy Prime Minister Nguyen Chi Dung.

The U.S. tariffs, among the highest on any of the targeted 180 economies, "did not reflect the strong bilateral relations between the two nations", state broadcaster Vietnam Television reported, citing Chinh.

In a government statement released after the meeting, the prime minister urged the U.S. to implement policies that align with Vietnam's status as a developing country and its recent efforts. He did not elaborate.

"This is an opportunity to restructure the economy towards swift yet sustainable development... to expand markets, diversify product markets and supply chains, and boost localisation," Chinh was quoted in the government statement.

The statement reiterated that the "GDP growth target of 8% or more in 2025 remains unchanged."

The U.S. is Vietnam's largest export market, and in 2021, exports to the U.S. were valued at $142 billion, nearly 30% of the country's GDP. Vietnam's trade surplus with the U.S. exceeded $123 billion last year.

"It's a shock for the global economy, and for the Vietnamese economy," said Vo Tri Thanh, a former deputy director of the Vietnam Institute for Economic Management.

Following the announcement from the White House, Vietnam's benchmark stock index had fallen as much as 6.7% as of Thursday afternoon to 1,229.

In a bid to reduce its trade surplus with Washington, Hanoi had recently taken measures, including cutting tariffs on a wide range of goods destined for the U.S.

At Thursday's meeting, Chinh ordered the immediate formation of a task force to manage the situation and said he planned to hold discussions with major export firms. (Reporting by Khanh Vu, Phuong Nguyen and Francesco Guarascio; Editing by John Mair and Kate Mayberry)