By Andrew McCathie, dpa

Washington DC – US President Joe Biden and German Chancellor Angela Merkel meet in the White House on Thursday as part of efforts to renew trans-Atlantic ties after the tensions unleashed by his predecessor's "America First" administration.

The chancellor is set to begin the day in Washington with a breakfast meeting with US Vice President Kamala Harris before talks with US business leaders and receiving an honorary doctorate from the Johns Hopkins University.

Merkel's US trip is also likely to be one of her last foreign excursions as chancellor before she leaves the world stage at September's national election, when she stands down as leader of Europe's biggest economy.

The chancellor has made more than 20 visits to Washington during her 16 years in power, with Biden now the fourth president to occupy the White House since she came to power 16 years ago.

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The Biden-Merkel talks are expected to focus on steps to end the global coronavirus crisis, the post-pandemic economic recovery, climate change, as well international security issues such as the seven-year conflict in eastern Ukraine.

Merkel's White House meeting is also likely to include talks on the controversial Nord Stream 2 gas pipeline aimed at supplying Russian natural gas to Europe via Germany.

The $11-billion pipeline project has been a source of US-German tensions, with Washington arguing it poses a security risk by increasing Europe's dependence on Russia.

Merkel has built up a formidable reputation in Washington, with former US President George W. Bush this week commending her leadership skills.

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"Merkel has brought class and dignity to a very important position and made very difficult decisions," Bush told German broadcaster Deutsche Welle.

Underlining Merkel's links with the US, Bush's successor, former US president Barack Obama, awarded Merkel in 2011 the highest civilian honor in the US, the Presidential Medal of Freedom, praising her as a "trusted friend."

But after developing a very close working relationship with both Obama and Bush, Merkel's ties with president Donald Trump were badly strained after he attacked her liberal refugee stance as well as Germany's trade and industrial policies.