Nato secretary general Jens Stoltenberg has said he is confident differences with Turkey over a new alliance defence plan to protect the Baltic states and Poland can be resolved.

Turkish President Recep Tayyip Erdogan has threatened to block the plan after criticism of Turkey's incursion against the Kurds in northern Syria.

But arriving for a meeting of alliance leaders near Watford, Mr Stoltenberg said: "I am confident that we will find a solution to the updating of the revised defence plan."

He said Nato leaders would for the first time discuss the rise of China, which was now the world's second biggest spender on defence.

"This provides opportunities and also challenges," he said.

Shadow international development secretary Barry Gardiner has warned against interventions in foreign conflicts by saying "you don't start bombing before you started thinking".

Speaking to BBC Radio 4's Today programme, Mr Gardiner insisted Labour is "committed to Nato," when asked if the party's leader Jeremy Corbyn supported the alliance.

Asked to confirm Mr Corbyn's own views, Mr Gardiner added: "You want to personalise things, I want to talk about policy, I want to talk about what's in our manifesto."

He continued: "The way you defend this country is by ensuring that you don't go on foreign wars, you don't start bombing before you started thinking.

"Consistently, if you look at the Iraq war, who was on the right side of history about that? Jeremy Corbyn was, not the president at the time, and indeed not the Labour Party at the time under Tony Blair.

"But all of Parliament went into that, Jeremy Corbyn did not."

Boris Johnson has played down divisions in Nato amid differences over Turkey's incursion against the Kurds in northern Syria.

Arriving for the 70th anniversary meeting of Nato leaders near Watford, Mr Johnson said Britain's commitment to the alliance remained "rock solid".

"Clearly it is very important that the alliance stays together, but there is far, far more that unites us than divides us," he said.

Mr Johnson said he had a "very good" bilateral meeting with US President Donald Trump on Tuesday evening.

"We discussed the future of Nato, we discussed what is going on in Syria and various other matters," he said.