Image caption Shinzo Abe is the fifth Japanese leader Barack Obama has met in office, and Abe has previously visited the White House

US President Barack Obama and Japanese Prime Minister Shinzo Abe have affirmed their security alliance and pledged to stand firm against North Korea.

At the White House, they said the two powers would co-operate to promote regional stability and economic growth.

Mr Abe, elected in December for his second stint as Japanese leader, said Japan would proceed in a "calm manner" in a territorial dispute with China.

He said "the trust and the bond" in the US-Japan alliance was restored.

In remarks to the press after the Oval Office talks, Mr Obama said the alliance between the US and Japan was the "central foundation for our regional security and so much of what we do in the Pacific region".

Mr Abe said both countries had to take a tough stance on North Korea, which recently conducted a third nuclear test.

"We agreed that we would co-operate with each other in dealing resolutely with North Korea," Mr Abe said.

Mr Abe is serving as Japan's top leader for a second time, after a brief period in power in 2006-7. He is the fifth Japanese prime minister that Mr Obama has met in office.

'Strengthen our alliance'

His visit is seen as a bid to shore up a security partnership between the two countries that goes back decades.

"We intend to continue to strengthen our alliance," he said.

Following the visit, the White House released a joint statement saying the two countries would continue negotiations over Japan's entry into the Trans-Pacific Partnership (TPP), a proposed free-trade agreement between countries in North America, Asia and South America.

Japan has discussed becoming part of the TPP over the years. But this has been met with opposition from farmers, who say that tariff removals will have an a negative impact on their industry.

Ahead of the visit, Mr Abe said US support was critical in a bitter row between Japan and China over disputed islands in the East China Sea.

Both Beijing and Tokyo have ships in waters around the islands - known as Senkaku in Japan and Diaoyu in China - leading to fears of a clash. Japan controls the islands, which are also claimed by Taiwan.

US-Japan ties were strained somewhat under the previous Japanese Democratic Party (DPJ) administration amid a row over the relocation of a US military base in Okinawa.

But Mr Abe, who heads a Liberal Democratic Party administration, has spoken out about the need to prioritise the Japan-US alliance amid a changing regional dynamic.

After the meeting, Mr Abe and Mr Obama dined with US Vice-President Joe Biden.

Mr Obama said the leaders would discuss economic co-operation and steps they could take to encourage growth.