Streaming services like Netflix cannot be relied upon to keep investing in British programming, the BBC’s director general has said, in a stark warning about the consequences of scaling down the corporation.

In an impassioned defence of the broadcaster, Sir Tony Hall also said there was no guarantee that such services would continue to finance content that “truly resonates with the lives of British audiences”, as he claimed that their commitment to British programming did not come anywhere near that of the BBC.

He also warned that without the corporation, streaming services providing content from outside the UK would squeeze out “our own, distinctively British culture”.

His plea, in an essay for the parliamentary magazine House, comes after threats to the corporation’s scope and licence fee, which costs £154.50 a year. A new fee agreement is due in 2022. The BBC has faced a series of challenges in recent times, most notably the arrival of subscription streaming services. Greg Dyke, the former director general, is among those to have described the licence fee as an anachronism. Oliver Dowden, the new culture secretary, has suggested that the funding and purpose of the BBC need to be examined.

Hall writes: “It’s true that some of the global streamers are now doing more to invest in some British content. But it comes nowhere near matching the BBC, and is there any guarantee it will continue? I wouldn’t like to bet on it.

“Even where the big global streamers do invest in the UK, there is no evidence that they will support the breadth of British content that UK audiences rely on. Nor is there any guarantee they will make content that truly resonates with the lives of British audiences. Cultural influence from across the Atlantic is great if it adds to our choice. It is less great if it comes at the cost of our own, distinctively British culture.”