Prime Minister Bill English will wind up his trip to Europe after a meeting with German Chancellor Angela Merkel - the most powerful leader in Europe - in Berlin tonight.

LISTEN ABOVE: NZ Herald reporter Claire Trevett spoke to Bernadine Oliver-Kerby from Europe

New Zealand Herald deputy political editor Claire Trevett told Bernadine Oliver-Kerby free trade will be high on the priority list.

"Merkel is the most influential leader in Europe and if we get their backing for the free-trade agreement, and they have already expressed support, then thunderbirds are go

English was keen on hearing Merkel's take on migration and security issues in Europe, as well as the heightened tensions on the border between Russia and Europe.

"She and Germany are at the fulcrum of the major tensions in Europe - the migration issues, security issues with Russia, the economic issues. So I'm very keen to hear how she's thinking about those because the decisions that she makes will have an impact on New Zealand eventually."

He also wanted to ensure Merkel and Germany were still supportive of the free trade agreement with New Zealand.

"They've been strong supporters of the free trade agreement between New Zealand and the European Union so we want to affirm that support and make sure it is going to be ongoing through the process.

As the de facto leaders of Europe, we have very much appreciated that support."

English will be given a welcome including full military honours at the Federal Chancellery.

It comes after three days of meetings in London, where English had briefings from key business leaders and ministers, including Brexit minister David Davis and Secretary of State for International Trade, Liam Fox.

It was not all work and no play for English in London. He and wife Mary took the opportunity to go to the Carole King musical. He insisted he had not sung along. "I behaved in a very Prime Ministerial manner."

English also caught up with former PM John Key, who was in London on his way to Munich for an International Democratic Union meeting.

Key kept a low profile in London and did not attend any of English's events, including a reception at NZ House.

Asked if Key had given English a verdict on English's handling of his first international foray in the top job, English grinned. "He thought I was going very well - almost as well as he would have been."

- NZ Herald