The US and China have reached a deal to partially ratchet down their trade war, ushering in a fragile detente in their economic relations after 20 months of on-and-off negotiations and tariff escalations that unsettled markets and damped global growth.

The agreement, which was confirmed by officials in both Washington and Beijing on Friday, commits China to buying at least $40bn of US agricultural goods annually, tightens protection for US intellectual property and bans the forced transfer of technology from US companies.

It also contains commitments on the Chinese side against competitive devaluations of its currency and measures to improve access to its market for US financial services groups. However, China did not make concessions on some of the biggest sources of strain in the bilateral relationship, such as its use of industrial subsidies and state-owned enterprises, as well as cybertheft, leaving those thorny issues to a later stage.