Moneyfacts data shows that 1,304 buy-to-let products were taken off the market in March.

At the start of March this year, there were 2,897 to choose from. Today that number stands at 1,593.

In real terms, the mortgage type to suffer the biggest loss of products were five-year fixes across all LTVs, where 444 were removed from the market – from 1,00 to 556. The second biggest dro was seen in two-year fixes at all LTVs, where a drop from 914 to 507, a 407 difference, occurred.

Proportionally, the biggest loss was in fixed-rate BTL at 80 per cent LTV, where the number of products fell nearly 90 per cent – from 150 to just 16, and two-year fixed rates at 80 per cent LTV fared little better, losing 87 per cent, from 141 products to 19.

In terms of average rates, two-year fixes at 60 per cent LTV saw a jump from 1.89 per cent to 2.24 per cent, a 0.35 per cent upward change, and the biggest.

Meanwhile, average rates for two-year fixes at all LTVs dropped from 2.77 per cent to 2.58 per cent, and five-year fixes at all LTVs, from 3.24 per cent to 2.98 per cent.

Moneyfacts financial expert Rachel Springall says: “It is clear as day to see how the virus pandemic and isolation rules have led to a huge shake-up in the choice and cost of BTL mortgages. This couldn’t come at a worse time, as from this new tax year, mortgage interest tax relief has been completely phased out for BTL landlords.

“The fall in choice and rise in interest rates will be a blow to landlords who are considering investing. However, the market has moved in this way to protect providers’ existing books. Even if some believe the property market to be ripe to invest in, prospective borrowers who don’t have a decent deposit could well be discouraged.

“The optimism seen at the start of this year for a prosperous BLT market in 2020 could well have waned in light of the virus, and as margins grow tighter, it’s vital landlords consult a financial adviser and keep in regular contact with their tenants to get through these uncertain times.”