Foreign Secretary Boris Johnson said 16 named military officers and scientists would be subjected to travel bans and have their assets frozen when ministers meet in Brussels later today.
Mr Assad has denied the accusations that he sanctioned the use of chlorine bombs and sarin nerve gas.
It will take the total number of sanctioned individuals up to 256 since the start of the Syrian conflict.
A total of 67 organisations have also been sanctioned.
Mr Johnson said: “The UK condemns the use of chemical weapons wherever and by whomever they are used and we will continue to work closely with our international partners to hold perpetrators to account.
“The 16 individuals sanctioned include military officers and chemical specialists responsible for abhorrent chemical weapons attacks on innocent men, women and children.
“The UK helped push for these sanctions which send a clear signal to the Syrian regime that their barbaric actions have consequences.”
According to the United Nations (UN), there were at least three incidents in Syria in 2016 where chlorine was used by the regime.
In April this year, around 100 people were killed and many others injured in Khan Sheikhoun following a sarin nerve gas attack.
The move could bring some friction with French President Emmanuel Macron who signalled a change in France’s policy towards Syria.
During the recent visit by US President Donald Trump, Mr Macron indicated that the position taken by Paris would no longer include the removal of Mr Assad.
In a joint press conference Mr Macron said: “We have changed the French doctrine with regard to Syria; our fundamental task now is to eradicate terrorist groups, no matter [where] they are.”
The move would appear to bring Paris closer to Russia who do not want to see the Assad regime toppled.
After the seventh round of peace talks which concluded on Friday in Geneva, Russia’s ambassador to the United Nations (UN) Alexei Borodavkin said: “The essence of this correction is that during this round…